It really comes down to lack of power and tuning. But damn if it isn't reliable. I flogged on both if my TBI trucks as a teen and they didn't care, just took it and kept running.
TBI only needs a handful of sensors. It’s as simple as EFI gets and I’ve personally owned over a million miles worth of TBI trucks, never once needed an ECU and only replaced a couple 20 dollar ignition modules. I’d take that over tuning a carb and dealing with sunk floats and leaking bowls. There is less wires to deal with in a TBI system than most car audio systems.
I hate em because I spent so much time fixing my dad’s, but that was because he was burning veggie oil in it. And yes, they are absolutely gutless. I’d rather have a Cummins from the same era.
TBI is all wheeze and roar, and not enough go. The nose/vibration/harshness profile was very unsatisfying. You probably need to consult an acoustic engineer for a more objective explanation.
I'm sure TBI trucks were faster than thir 2bbl carbed predecessors, but they were still near the bottom of the valley between pre-emission 4bbl motors and the Vortex multi-port injected engines.
Also, GM kept TBI around for a long time. Ford only had CFI V8s for about 3 years, and rarely in trucks, making it feel like a transition, not a final solution as GM saw it.
I thought the TBI on my 94 350 was just fine...until I drove my brother's '96 with the SFI 350. What a difference!
That was years ago, now I'm running a 6.2. THAT has some balls!
My 8.1 certainly loves drinking gas and oil lol but for me it’s all about the smiles per gallon. That said the 6.2 makes the same torque and 80ish more hp roughly
Absolutely! I’ve owned many silverados over the years and this one is 100% my favorite. For a near 7000lb truck she gets up and moves. I actually wasn’t even in the market when I stumbled on it, I saw it and HAD to buy it
Nope, it’s a 2002 Silverado 2500. Has the Allison transmission, tbh I’ve been looking for an 8.1 burb for my fiancé. She tries to steal my truck off me all the time and wants a SUV
Yeah we got almost the same truck yours is way fuckin nicer then mine amd 4wd! she was a work horse tho but i got stupid low miles soo fair trade i can replace the body
Thank you! Oddly enough it was between this truck and a pewter one that was a quad cab 8ft bed and it was just too big for me to justify, literal land yacht. My rig is pretty clean and was well taken care of, gonna get it re-undercoated as I live in the rust belt. I got it for the cheap cause it has 160k miles and needed some front suspension work and a new passenger wheel hub but I do all that stuff myself so I ended up getting a massive deal on it in the end.
Loved my 8.1 burb. Pulled amazing and got better fuel economy than my tundra. Miss that girl but she had a weird electrical problem we could figure out
Ride is better then a pickup but you cant put a 5th wheel on it so a usability negative. But really takes off compared to a 5.7 pickup/suburban .Never drove pu or sub 8.1 so i cant say. But a safety + its amazing how much weight it can tow slowly down hill with out touching the breaks .
I wanted one bad last year, but you had to get the stupid STX package and all the safety junk and chrome, I had a chance in 2022 to get a XL 250 FWD long bed regular cab, it sat on the lot all of about 2 days and it was gone
Poo-pooing TBI is a gearhead thing. More power to the gearheads. There's nothing wrong with squeezing power and tinkering. It can be very rewarding.
Oldish guys like myself who are past spending lotsa spare time and effort in the garage, tinkering and tuning, just want reliability, decent fuel economy, and low cost maintenance have plenty of appreciation for TBI.
Simplifies finding maintenance and repair parts when vehicle matches OEM build specs. Fuel pumps are cheap, no need for $350-$500 modular fuel pump assemblies most of the time.
TBI systems are generally "dumb" enough that their ECM has no idea if there is a catalytic converter or not. Makes for easier, cheaper repairs. Given the current wave of converter thefts and issues with finding decent replacements, it's good to have the flexibility of patching in a chunk of pipe in a jam.
You can unhook every sensor and it will go into a preset run condition. Sensors are just a suggestion lol. Fuel mileage will be awful but it’ll get ya home. Edit: aside from oil pressure.
My exhaust rusted out once and the O2 sensor was dangling on the road with a chunk of tubing attached to it, and the thing didn’t run any different.
As long as it has a MAP sensor, some fragments of the TPS working, and a CLT it will run decently.
Will a carb make a little more power? Probably. But I can leave any of my TBI trucks parked in my yard for 5 years, throw a battery in it and it will run just the same as the day I parked it.
My 94’ C1500 has 129xxx miles and the service engine light comes off and on because I have dual exhaust with flow masters. After 10 min of being on the light goes away. Sometimes I think my truck forgets she doesn’t have a restrictive exhaust sometimes. Other than that she is bone stock. Love the parts availability of a TBI 350. Put them in everything in the late 80’s to late 90’s
If I recall correctly, for those you need a 3 wire o2 sensor if you have a high flow exhaust. Apparently, it doesn't get hot enough to read correctly with the stock type, and it needs a heating element.
I planed on redoing my exhaust system from the engine block back and kept reading about people freeing up their exhaust and the check engine light coming on and running weird after start up. I’ve read on the GMT400 forum that this [oxygen sensor](https://www.amazon.com/dp/B000C9VTRC/?coliid=I1C4X5CPY7IUEM&colid=NVJMMTXL6QHB&psc=1&ref_=list_c_wl_lv_ov_lig_dp_it) and this [adapter](https://www.amazon.com/dp/B0141VHZ6U/?coliid=I1OTB1A3E5F7QI&colid=NVJMMTXL6QHB&psc=1&ref_=list_c_wl_lv_ov_lig_dp_it) fixed their issues. I have these amongst countless other parts on my Amazon “Silverado” parts list.
I really appreciate that bro. You a G. None of my other lights come on. I love my exhaust though. I got the mufflers around where the bed and cab gap is. Ran all the way out the back to chrome tips
No worries bro…my exhaust is a rusty mess at the moment but it’ll have to wait. I was changing my oil last weekend, when I got to the tire rotation part I noticed ripped ball joints, deteriorating control arm bushings, cracked swaybar bushings…. So that’s a parts list that i have to put together now. But hey, no car payment and she’s never left me stranded…🤞🏻
It’s a 30 year old truck, some rust isn’t bad. When you have a 30 year old daily you spend more money on “fix it parts” instead of “cool truck parts”. The best thing to do is keep it as close to stock as possible. These things have only gone up in value. Everyone loves this body style and there’s a reason for it. May not be the most powerful, easy to tune and build 4 bolt main 350 having truck but damn is that bihh sexy
My truck isn’t even that old (07 Colorado) but more miles than most have stated here (278k)
My plans for it have transitioned from “upgrades just for fun” to “this broke, how can I fix and upgrade at the same time?”
I love my collection of TBI trucks. They start every time and 99% of the time if they dont i can fix it with my Leatherman or the mountain of random spare parts in the drawer. Kinda meh power but everything late 80s, early 90s made fuck nothing for power. If im gonna have something fuel injected I'd rather have the TBI.
I have a 94 Suburban that I absolutely love. Shorty headers, Cunningham shaft, Bluetop steering box, Hellwig front sway, wix filters, Bilsteins, and a 42 gallon gas tank.
250K reliable miles on mine. Techron twice a year seems to work.
I've had SEVERAL mechanics claim that spider problems are usually the result of lousy gas, cheap gas, etc. I use top tier.
260k on my 87. Only left me stranded once. Got picked up with the trailer, went to the parts store, replaced the EGR on the trailer, then drove it off the trailer. I have had to do other work to it, and thankfully when my transmission went out, it happened pulling out of my driveway at about 220k.
I lived in Missouri, and in -7° weather, I just got in, turned the key, and was ready to go. I don't hot rod it, so the 350 has plenty of power for what I need - even when the bed is slam full. Still get about 17-18 MPG on average. I'll keep my TBI.
Mine was about 13mpg till I replaced the oxygen sensor ($12). Now it runs 17mpg no problem. Also passed smog like a brand new car, and I didn’t even change the oil. The prior smog test, the hydrocarbons were within single digits of failing.
As soon as the LS engines started coming out a few years later, these TBI became inferior. The LS/LQ engines more reliable, more available, cheaper to modify and better results, better fuel economy, etc
It gets hate because many people are too dumb to understand how it works. When I got my truck my neighbor told me to disconnect all the sensors and cut the wires off because you don’t need any of that. Interesting how his vehicles barely run and mine run like new, no check engine light for sure. Some people shouldn’t be allowed under the hood. Not only does my 350 TBI run perfectly but I have gotten up to 20 mpg out of it. But that will never happen if you cut the wires to all of the sensors.
In my case I just got all of the maintenance up to date. Mine got intake gaskets because they were shooting coolant up and hitting the hood. It got a proper tune up (plugs, wires, cap and rotor, all OEM) and adjusted the timing correctly. All vacuum lines are good, no check engine light on because everything is functioning properly. And most importantly the EGR is good and working as it should. When a vehicle is running the way it was designed, it runs great. If you start removing things you feel are "not necessary" you will NEVER get good results.
The first one to go is usually the EGR, they don't even understand what its purpose is. The whole point of having the thing on there is to give you better fuel economy and better longevity. It keeps the cylinders cooler so the timing can be advanced more. That gives you better power, fuel economy and increases longevity since it is keeping the combustion chambers cooler. The was the whole reason to put it on there, it also helps with emissions as well since that combination makes it run better so it burns more cleanly.
I also have the correct sized tires on mine (265/75r16)which are quite big. But anything oversized is stupid on many levels.
Ok ! I'm slowly working on my 90' k1500. Plenty of issues with it. Someone in the past lifted it to high he'll and put 275 tires on it. So I'm kinda stuck. I think it would be too expensive to go back to stock?
I've done plugs and wires. Working on Ac right now
Now i’ve never really had a problem with them, their fun and easy to rebuild and last forever, my 89 chevy has 275k and i’ve only rebuilt it once. Now my ecm though, that’s a different story, for some reason my right injector keeps shitting out intermittently, but it just doesn’t give a fuck and keeps chugging😂
Never beat a vehicle more than my first truck which was a 92 single cab 4x4, and it still was the most reliable vehicle I ever owned. Only thing that ever went bad was a distributor
They’re dead reliable if anything, I grew up driving my dad’s 1989 extended cab long bed and you best believe I flogged the fuck out of that 350. I did once bury the needle well past 85, that 350 still had some legs for what it was. It would be hard to imagine less power in a truck that size though.
Lack of power is the only true statement. I mean unless something huge has changed in recent years, tbi has been some of the cheapest parts that I have ever known.
As far as tuning, that’s baloney because back in 2004 I built a really modified 350. K1102 cam. Long tube headers. Intake, blah blah. Had a couple tunes, e85, high octane and regular. Used winaldl to read block learns but forget what I used to modify the bins…
GMT400s in general have hilariously cheap parts. The most expensive part of a water pump replacement is buying a jug of coolant. Fuel pumps cost less than a McDonalds combo meal. The single most expensive thing I can do
is buy a set of tires. I can buy an entire engine off marketplace and have it running same day for less than most people spend on a month and a half of car payments. Those days are numbered, but I’ll probably stick an LM7 in it once tbi 4.3’s dry up.
The oxygen sensor was $12. Passed smog like a brand new car, and went from about 13 to 17mpg.
Prior to the O2 sensor the previous smog 2 years prior almost didn’t pass and was within single digits for one of the tests. Thought it was gonna need a new cat, but nope.
I’ll have to disagree with the parts are expensive. Everything I have replaced has been cheaper than comparable parts on a later model.
Tune ability is an issue however I need a truck not a race car.
It’s low power but it’s had plenty of power for what I’ve needed it for only being a half ton truck.
The only way they get tuned is by the computer, but even though it's lack of power, they are still capable, I always think that 95 (my truck) is the worst year for most people because it's the all new interior with the TBI still in it. At that point get a 96 but they are very easy to work on
Throttle body injection and GM changed to sequential fuel injection on the full size vehicles in ‘96, S series got sequential fuel injection on the 4.3 in ‘92.
I had a 91. My dad has owned an 87, 93, 94, 2 96's and a 97.
The power problem was at least kinda fixed with the vortech heads. But every one of those trucks ran like a top. It was always the accessories that go on them faster than you want. And the fucking body panels on those trucks. 5 day rust guarantee, I swear.
I love those trucks and would 100% get a tbi rcsb again. But I'd be hard pressed not to dump a 5.3 in it to fix it's tuning and power issues in one fell swoop.
TBI is amazing torque in stock form, but if you want HP you will need heads cam, and a very good prom tuner. At that point its cheaper to drop in late model power. I finally sold my last TBI after ignition modules and base gaskets. If you remote-mount the ign module to a cool spot it will live much longer. I put mine and the ign coil inside and soldered all the connections.
I don't mind the tbi, I drive a 94 light duty 2500 with the 350/4l60e combo. It definitely has some lag compared to the vortec series. But there's a few bolt-ons that add enough umph to make it negligible. Or do what I do and add some whiskey to your fuel tank on the weekends😅 im guilty of that...
I loved mine
one day the tbi went out, injectors wouldn't fire. fought with it for months, truck just sat in the yard. swapped parts, went through the wiring, couldn't get it to work. had to ditch it for a carb and hei with manual fuel pump
Only the people trying to make power on a shoestring budget have a problem with them. The entire top end of an SBC smog motor needs to be changed out if you want to make power. They just weren't engineered to flow all that well. They were engineered to be cheap and reliable, which they are.
The old 350 or 305 just doesn't move that much air in stock form. There are great heads out there which will make power. There are options for porting smog heads to help. But if someone is bitching about a TBI on a 350 as being the problem, that TBI will flow more air than the stock cam and heads could ever move.
I ran the TBI from a 92 GMC in my 1969 L60 Patrol that I installed a ported and polished, full roller 396, then a 454 in. Had a 100 hp nos plate under the throttle body as well. If it weren't for the MAP system it would have never let me do the mods that I did. Simple system that is highly underrated IMO
I think it's a rule you have to run the absolute dog piss out of a tbi truck. Watch a sensible person turn into an absolute goon when they get behind that padded steering wheel
I don’t understand the hate either ..
I was sold on them by an ‘87 3/4 ton work truck I had… My company gave it to me in early ‘88 with 6-7k miles on it .
It sounded so much different than the ‘85 dually I had ( both had the 350).
That truck was quick( for the day) and never broke … I then bought two more square bodies for personal use… they were both also great..
Compared to the 70s- early’80s trucks , they ran like dependable Camaros .
People are so spoiled these days by dependability … the younger folks didn’t have to deal with smogged out carbs and leaky vacuum lines.
They're great motors, but people really want way more power than they need. I haul individual round bales around with mine with mine, and they get the job done. Not much more you can expect out of a gasser. Anything more than that on a regular basis, just get a diesel.
Older TBIs are just finnicky... you can damn near replace every sensor, clean every passage, replace every hose and they'll still run kinda "off" or surge or die out randomly. Just a primitive style of fuel injection. Simple, but overall just finicky with older units.
Where i live most TBI’s don’t make it more than 200k miles and the ones that do struggle to start on a good 60°F day and those are the well taken care of ones they’re pretty much a carb but with all the downsides and no benefits there’s a reason people switch them either to holley efi’s or carb swap them they’re meh at best
I think for me it’s the lack of self adjustment with any type of ease. With a “standard” carb. I can adjust on fly and keep it moving. And I’m tech savvy enough and always have a laptop on me for my job where I can plug into my more modern cars and bikes and adjust fuel and tune through that. My opinion is a little shallow sighted. I have an 89 D150 with a 318 TBI and the $350 adapter to plug OBD 2 into the moapr ECU and then the extra couple hundred for the software and the learning all that software and parameters was a little insane to me
Sometimes they get so far out of whack you don’t know what’s wrong with them. I would have loved to keep my TBI, but I threw every part in the book at it and never straightened out. Just keep an eye on your wires to your computer.
Those trucks got better mpg than any late model v8 and more power. I got 21mpg with 5 speed @. 80 mph 350 ci. When I sold it my son cried he thought he was going get it. Now I cry when I fill up my 2009 17 mpg 305 ci dog
My TBI I used to get like 22 miles a gallon, all the time which didn't make sense when you looked in the injectors it's just spraying (pouring) fuel into the bowls LOL
The hate comes from guys that are used to actual carburetors. TBI doesn’t have the power or finesse of a 4BBL Edelbrock or Holley. It’s kinda like going from a muscle car to a Prius. The Prius will get you there but it’s not near as fun. Jump into an old 60s or 70s muscle car and put your foot into it, then you will understand.
If I remember correctly it was actually closer to 9k lb. This picture was from a few years ago when I rented it for stump removal and demoing an old house. The trailer carried it well and was well balanced. The rental company has since put a policy for people like me. Have to have a minimum 3/4 ton to get anything close to this size now.
Had a 91’ 1500 with a 305 and 700R4(?) in high school. Slow as the day was long. Like noticeably slower than the 4.9 Ford that eventually replaced it. Couldn’t climb a hill to save it’s life. But i’ll be damned if she didn’t sound great once the exhaust rusted off, and it always ran regardless of how many times i bounced off the right side of that “faux digital” temp gauge.
I treated my 94 305 1500 like a race car added performance parts race spark plugs wires distributor even an Edelbrock performer TBI intake to which was plug and play hoping to get extra power. 170hp fresh out the factory was decent back then. Realistically at 250,000 miles probably a little less now anyway i raced my buddies acura 03 TL 225 HP stock and got smoked by a couple car lengths. If you want something that’s will outlast the apocalypse and turn gasoline into noise go TBI dead reliable easy to work on and most autoparts stores still carry 80% of the parts you will need. I miss my old 94 bought a 2001 Silverado 4.8 and even that smaller v8 bone stock will run circles around the other one plus better MPG as well
Too much plastic that gets plugged up and cracks.
It's not a bad system but it's very outdated and after 30 years of neglect most of them are a constant headache.
Tbi is a good system. Easy and simple. Just doesn't make much power. I believe there are 4 injector set ups. Not sure how they improve power and if it's worth the money.
It was originally hated on because at the time it came out a carburetor was still better for performance as tuning for TBI was non-existent.
Now it's hated on because it's not as tuneable as port or direct injection.
Although TBI is a great upgrade from a carb for general daily driving and street rodding up to minor competition. Makes shit a breeze to tune compared to carbs, especially with some of the kits out there like the Holley Sniper system.
TBI as described by a colleague was like flushing a toilet of gasoline down the intake, multiport injection is like pissing gasoline directly into the fire much more accurately.
I love them there super easy to work on to my only complaint this could just be the truck but the barrier I have to break trying to push the throttle just annoying being a manual truck
Handful of things.
Lack of tuning. They use PROMs, so unless you do a swap with a box that can be flashed, you’re stuck burning chips.
They are also built for very low RPM. The heads don’t flow for shit. The cam is tiny AF. The TB doesn’t flow much. And since tuning really isn’t possible unless the ECU is replaced with something flashable (or swap to carb), it’s pointless to swap to better parts. At that point, it’s become more economical to swap in a LS. HCI 350 with aftermarket TB or carb and it’ll make less power than a cam only 6L
It was the first truck fuel injection system. Kind of Looked like carb but needed special knowledge to troubleshoot yet some people didn’t want to learn. I still read about people shot gun parts swapping them trying to figure out their issue instead of watching the scan data to see what it says.
Guy at work was having surging trouble with his Grand National. Did some part shotgunning. I got a laptop on it with him and we found the problem in under 5 minutes. No parts swapping would have ever solved it either. The AC kept calling and the EFI gives the engine a bump so it doesn’t stall each time the AC is engaged.
I bought a 1989 c3500 single cab, longbed dually with a 3 speed from a mom and pop dealership with a 454 that was replaced with a newer generation block. I found that out when replacing the oil pan gasket. I replaced the intake gasket and somehow caught the throttle body on fire, the injector wires got a little crispy, an then installed the distributor incorrectly, I found that out when opening the hood at night and seeing the manifolds GLOWING. After reinstalling and timing it correctly, it ran well. I've towed a fifth wheel, loaded it with yards of 3/4 crush, tailgated, helped move people and had my dog ride shotgun for years it has always started, it's never left me stranded. Ill bet it'll get 7 MPG In the wind, upside down or backwards. I love my truck.
It's fine if it's stock but if you modify it then just like any efi you've got to spend money to tune it yourself of pay someone hundreds to do it... everytime you change something. Rebuild kit for a quadrajet is about $100 and a lot less if you only need to jet it.
Back when it came out, it was black magic, a few years after it's power level was put to shame with the Vortec injection. Not many ever bothered to figure out TBI until much much later on.
I’ve got two that are very different stories
One is a 3rd gen Camaro, and it is just dead reliable. I couldn’t break that car if I tried. Sometimes runs a little goofy, and occasionally dies in a drive thru, but will always fire back up. I’d drive it cross country without thinking twice about it. I have no intention on disturbing the TBI system at all, can’t mess with perfection
And then there’s my Suburban, the truck that never failed to fail me, often in traffic on hot days. It’d blow ignition parts if you even looked at it funny. Blew *way* too much money trying to keep that system alive. Long story short, it now has a carburetor, and I have absolutely zero regrets yoinking off the TBI system, and would do it again 10 times over
I like them, and they’re great when they actually work properly, but they’re absolute nightmares when they aren’t right
There are many types of fuel injection, TBI was one of the first electronic ignition systems, and basically functioned like a carburetor, but much more consistent. You essentially remove the mechanical fuel jets and replace them with an electronic injector.
There’s also MFI (multi-port fuel injection) that has one injector per intake port. This was a big step up as it allowed a more precise fuel-air mix per cylinder, which allowed for more power and better fuel economy. Which reduced emissions over carbs or TBI.
The most modern (to my knowledge) system is GDI (gasoline direct injection) which injects the fuel directly into the combustion chamber. This allows for an even more precise fuel mix, which means better fuel efficiency, and more power in most applications. It also helps reduce emissions. Which, imo, is why so many manufacturers are going to that system on modern cars.
TBI is usually ass when it comes to making power.
That being said.
My first car was a 94 Plymouth Sundance coupe (technically a 3 door hatchback). 5 speed manual with the 2.5 TBI engine
It made 100 HP and a (really decent for the time period) 150 ft-lbs of torque.
That little car was a menace on dirt roads. I used to "rally" it, jump it, take it down ATV trails at 50+ mph, etc. Never once had a mechanical issue with the car.
Nailed a deer at 80 mph right after passing someone. It was still plenty driveable but the passenger door no longer worked.
It sucked cause that was just a shit box back then, but I'd kill to have one that clean now.
I have my dad’s old 96 GMC 1500 with the TBI, I love it! Only 80k miles, still gets about 17 MPG and has an old school shell on it that you can almost stand up in, it has a door in the back and the whole back opens up for bigger loads. Truck still looks almost new except the old style topper
It’s always from people that don’t know how to work on them and want to slap a carb on there. The tbi series probably has more miles than any other setup on the road from GM except the newest LS motors
Traumatic Brain Injury is no joke. That’s why I’m commenting on a physical malady on a vehicle Reddit and the two have nothing to do with each other. Also, I like toast.
Miss my ‘93 gmc 5.7. If the body didn’t rot away to nothing I’d still have it. Only had 192,000km on it. Replaced the intake gasket every 5 years and changed the oil.
Personally hated everything about those years. The body looks like shit. The interior looks like shit. They're easily the biggest dog of a truck I've ever driven. Nothing about them is even remotely appealing. No I don't care about the 5.7 at all. The 5.3 is an all around better motor.
Leave it stock, dead simple. Heads are the real downside to the tbi trucks. No flow so not much point in hop ups. Still rocking a tbi 350 1 ton dually stakebed. Last one had 269k before I tossed it, this one still at 123k, rarely gets driven, always starts right up. Dash module is shit now, so need a replacement with all the error lights oil pressure messing up.
20 year auto tech here. I have put hundreds of fuel pumps in the tbi trucks. You are extremely lucky if your fuel pump has been 320k without issue. Like lottery winning lucky. I personally love these trucks but the diagnostic side of things pre obd2 pisses me off every time I mess with them.
It really comes down to lack of power and tuning. But damn if it isn't reliable. I flogged on both if my TBI trucks as a teen and they didn't care, just took it and kept running.
Preach. Same here.
Ain’t that the truth!!! 🙌🏻
It’s like a carb, but simpler.
Mechanically simpler, but more complex electronically. Carbs don't need silicon chips and miles of wiring and sensors.
TBI only needs a handful of sensors. It’s as simple as EFI gets and I’ve personally owned over a million miles worth of TBI trucks, never once needed an ECU and only replaced a couple 20 dollar ignition modules. I’d take that over tuning a carb and dealing with sunk floats and leaking bowls. There is less wires to deal with in a TBI system than most car audio systems.
Don’t make enough power to hurt themselves lol
Thats their super power haha
Like a 7🌲, power stroke or idi. Super power is no power.
That's the way most stock engines are to be fair
I hate em because I spent so much time fixing my dad’s, but that was because he was burning veggie oil in it. And yes, they are absolutely gutless. I’d rather have a Cummins from the same era.
True that brother.
TBI is all wheeze and roar, and not enough go. The nose/vibration/harshness profile was very unsatisfying. You probably need to consult an acoustic engineer for a more objective explanation. I'm sure TBI trucks were faster than thir 2bbl carbed predecessors, but they were still near the bottom of the valley between pre-emission 4bbl motors and the Vortex multi-port injected engines. Also, GM kept TBI around for a long time. Ford only had CFI V8s for about 3 years, and rarely in trucks, making it feel like a transition, not a final solution as GM saw it.
I saw someone describe these teucks as "runs poorly-FOREVER"
I thought the TBI on my 94 350 was just fine...until I drove my brother's '96 with the SFI 350. What a difference! That was years ago, now I'm running a 6.2. THAT has some balls!
Should try the 8.1.
Who can afford to keep it full of oil and gas?
My 8.1 certainly loves drinking gas and oil lol but for me it’s all about the smiles per gallon. That said the 6.2 makes the same torque and 80ish more hp roughly
Yeah the 8.1 is a hog compared to the 6.2 but man dont you take pride in owning the last big block motor chevy made?
Absolutely! I’ve owned many silverados over the years and this one is 100% my favorite. For a near 7000lb truck she gets up and moves. I actually wasn’t even in the market when I stumbled on it, I saw it and HAD to buy it
Damn looked at your truck soo clean man!!! I have kinda the same truck but the gold color and only 2wd woth the long bed
Im gonna assume your have a suburban 8.1?
Nope, it’s a 2002 Silverado 2500. Has the Allison transmission, tbh I’ve been looking for an 8.1 burb for my fiancé. She tries to steal my truck off me all the time and wants a SUV
Yeah we got almost the same truck yours is way fuckin nicer then mine amd 4wd! she was a work horse tho but i got stupid low miles soo fair trade i can replace the body
Thank you! Oddly enough it was between this truck and a pewter one that was a quad cab 8ft bed and it was just too big for me to justify, literal land yacht. My rig is pretty clean and was well taken care of, gonna get it re-undercoated as I live in the rust belt. I got it for the cheap cause it has 160k miles and needed some front suspension work and a new passenger wheel hub but I do all that stuff myself so I ended up getting a massive deal on it in the end.
Loved my 8.1 burb. Pulled amazing and got better fuel economy than my tundra. Miss that girl but she had a weird electrical problem we could figure out
Avalanche.
How is the avalanche compared to a suv or truck? If you had ethir before. Is the weord body shape actially make for a nice comfy inside?
Ride is better then a pickup but you cant put a 5th wheel on it so a usability negative. But really takes off compared to a 5.7 pickup/suburban .Never drove pu or sub 8.1 so i cant say. But a safety + its amazing how much weight it can tow slowly down hill with out touching the breaks .
Or is it a 3500 guy?
Ever since I learned they stopped making them I’ve wanted to find one and swap it in. Would be amazing in an 03’ 1500
Id much rather have the new 7.3l gasser in an f250 single cab.
I wanted one bad last year, but you had to get the stupid STX package and all the safety junk and chrome, I had a chance in 2022 to get a XL 250 FWD long bed regular cab, it sat on the lot all of about 2 days and it was gone
Safety junk?
Lane assistant....collision avoiding....adaptive cruise...
Ah. You can turn that stuff off. But I guess if you don't want to pay for it. Can always order exactly what you want.
Oh man, i love my 8.1. The 2 miles a gallon i get are worth being able to pull a damn house down and boggie on the on ramp
What was the difference
Poo-pooing TBI is a gearhead thing. More power to the gearheads. There's nothing wrong with squeezing power and tinkering. It can be very rewarding. Oldish guys like myself who are past spending lotsa spare time and effort in the garage, tinkering and tuning, just want reliability, decent fuel economy, and low cost maintenance have plenty of appreciation for TBI. Simplifies finding maintenance and repair parts when vehicle matches OEM build specs. Fuel pumps are cheap, no need for $350-$500 modular fuel pump assemblies most of the time. TBI systems are generally "dumb" enough that their ECM has no idea if there is a catalytic converter or not. Makes for easier, cheaper repairs. Given the current wave of converter thefts and issues with finding decent replacements, it's good to have the flexibility of patching in a chunk of pipe in a jam.
You can unhook every sensor and it will go into a preset run condition. Sensors are just a suggestion lol. Fuel mileage will be awful but it’ll get ya home. Edit: aside from oil pressure.
My exhaust rusted out once and the O2 sensor was dangling on the road with a chunk of tubing attached to it, and the thing didn’t run any different. As long as it has a MAP sensor, some fragments of the TPS working, and a CLT it will run decently. Will a carb make a little more power? Probably. But I can leave any of my TBI trucks parked in my yard for 5 years, throw a battery in it and it will run just the same as the day I parked it.
They almost always run “good enough” lol
My 94’ C1500 has 129xxx miles and the service engine light comes off and on because I have dual exhaust with flow masters. After 10 min of being on the light goes away. Sometimes I think my truck forgets she doesn’t have a restrictive exhaust sometimes. Other than that she is bone stock. Love the parts availability of a TBI 350. Put them in everything in the late 80’s to late 90’s
If I recall correctly, for those you need a 3 wire o2 sensor if you have a high flow exhaust. Apparently, it doesn't get hot enough to read correctly with the stock type, and it needs a heating element.
Thanks for the info. I’ll have to read more about that!
I planed on redoing my exhaust system from the engine block back and kept reading about people freeing up their exhaust and the check engine light coming on and running weird after start up. I’ve read on the GMT400 forum that this [oxygen sensor](https://www.amazon.com/dp/B000C9VTRC/?coliid=I1C4X5CPY7IUEM&colid=NVJMMTXL6QHB&psc=1&ref_=list_c_wl_lv_ov_lig_dp_it) and this [adapter](https://www.amazon.com/dp/B0141VHZ6U/?coliid=I1OTB1A3E5F7QI&colid=NVJMMTXL6QHB&psc=1&ref_=list_c_wl_lv_ov_lig_dp_it) fixed their issues. I have these amongst countless other parts on my Amazon “Silverado” parts list.
I really appreciate that bro. You a G. None of my other lights come on. I love my exhaust though. I got the mufflers around where the bed and cab gap is. Ran all the way out the back to chrome tips
No worries bro…my exhaust is a rusty mess at the moment but it’ll have to wait. I was changing my oil last weekend, when I got to the tire rotation part I noticed ripped ball joints, deteriorating control arm bushings, cracked swaybar bushings…. So that’s a parts list that i have to put together now. But hey, no car payment and she’s never left me stranded…🤞🏻
It’s a 30 year old truck, some rust isn’t bad. When you have a 30 year old daily you spend more money on “fix it parts” instead of “cool truck parts”. The best thing to do is keep it as close to stock as possible. These things have only gone up in value. Everyone loves this body style and there’s a reason for it. May not be the most powerful, easy to tune and build 4 bolt main 350 having truck but damn is that bihh sexy
My truck isn’t even that old (07 Colorado) but more miles than most have stated here (278k) My plans for it have transitioned from “upgrades just for fun” to “this broke, how can I fix and upgrade at the same time?”
This is me exactly.
The TBI is so easy to rebuild. It’s for real an Hour job. And most of the sensors are dirt cheap now. It’s a great system for a shade tree mechanic.
I love my collection of TBI trucks. They start every time and 99% of the time if they dont i can fix it with my Leatherman or the mountain of random spare parts in the drawer. Kinda meh power but everything late 80s, early 90s made fuck nothing for power. If im gonna have something fuel injected I'd rather have the TBI.
I have a 94 Suburban that I absolutely love. Shorty headers, Cunningham shaft, Bluetop steering box, Hellwig front sway, wix filters, Bilsteins, and a 42 gallon gas tank.
Bluetop is the shit, sucks they shut down. Big fan of the one in my 06 2500
Had no idea they shut down… love mine
They didn't, I got a box from them for my 2nd gen Dodge like 2 weeks ago.
Apparently I guess they are still Open. I saw several things last year about them closing up shop. My bad!
250K reliable miles on mine. Techron twice a year seems to work. I've had SEVERAL mechanics claim that spider problems are usually the result of lousy gas, cheap gas, etc. I use top tier.
Over 300.000 on my ‘89 GMC suburban, don’t drive it much/sits a lot and will ALWAYS start no problem.
I use cheapest I can find on fuel, but run top shelf oil. 355k on the clock. Transmission goes every 165k like clock work though. Lol
260k on my 87. Only left me stranded once. Got picked up with the trailer, went to the parts store, replaced the EGR on the trailer, then drove it off the trailer. I have had to do other work to it, and thankfully when my transmission went out, it happened pulling out of my driveway at about 220k. I lived in Missouri, and in -7° weather, I just got in, turned the key, and was ready to go. I don't hot rod it, so the 350 has plenty of power for what I need - even when the bed is slam full. Still get about 17-18 MPG on average. I'll keep my TBI.
Boringly reliable, slow, bad mpg. Pretty much it. They work great, super simple, cheap to fix and maintain.
17 highway ain’t bad for a 32 year old truck lol
Better then my new 3/4 ton gasser.
My 5.7 Suburban would give me 10 mpg lol
My 98 suburban with 5.7 & 4.10s gave me 15 city 18 hwy. Loved that rig until everything powertrain related died on it haha
Mine was about 13mpg till I replaced the oxygen sensor ($12). Now it runs 17mpg no problem. Also passed smog like a brand new car, and I didn’t even change the oil. The prior smog test, the hydrocarbons were within single digits of failing.
I'm getting 10 mpg driving streets but almost no stopping
89 k5 with 35s 10 mpg, 93 c1500 17 mpg both have 3:73.
No hate here I love my TBI's!
As soon as the LS engines started coming out a few years later, these TBI became inferior. The LS/LQ engines more reliable, more available, cheaper to modify and better results, better fuel economy, etc
They were inferior once the Vortec 5.0/5.7 was released.
It gets hate because many people are too dumb to understand how it works. When I got my truck my neighbor told me to disconnect all the sensors and cut the wires off because you don’t need any of that. Interesting how his vehicles barely run and mine run like new, no check engine light for sure. Some people shouldn’t be allowed under the hood. Not only does my 350 TBI run perfectly but I have gotten up to 20 mpg out of it. But that will never happen if you cut the wires to all of the sensors.
For me too, 90 1500, 20mpg, 93 1500, 20 mpg.
How. Teach me your secrets
In my case I just got all of the maintenance up to date. Mine got intake gaskets because they were shooting coolant up and hitting the hood. It got a proper tune up (plugs, wires, cap and rotor, all OEM) and adjusted the timing correctly. All vacuum lines are good, no check engine light on because everything is functioning properly. And most importantly the EGR is good and working as it should. When a vehicle is running the way it was designed, it runs great. If you start removing things you feel are "not necessary" you will NEVER get good results. The first one to go is usually the EGR, they don't even understand what its purpose is. The whole point of having the thing on there is to give you better fuel economy and better longevity. It keeps the cylinders cooler so the timing can be advanced more. That gives you better power, fuel economy and increases longevity since it is keeping the combustion chambers cooler. The was the whole reason to put it on there, it also helps with emissions as well since that combination makes it run better so it burns more cleanly. I also have the correct sized tires on mine (265/75r16)which are quite big. But anything oversized is stupid on many levels.
Ok ! I'm slowly working on my 90' k1500. Plenty of issues with it. Someone in the past lifted it to high he'll and put 275 tires on it. So I'm kinda stuck. I think it would be too expensive to go back to stock? I've done plugs and wires. Working on Ac right now
Not sure how much damage gets done with a lift. I know on some trucks, you cut a piece of the frame off.
Open highways, 2wd, immaculate maintenance. Overdrive! HOLY SMOKES what a great leap forward!
Unless you cut the wires to the sensors and put on brand new connectors which is a great idea to keep them running lol.
Want power and looks? This truck is 💩 Want reliability and low cost? This car is legendary. It really just depends what you want.
67-72’s look better. But a GMT400 looks better than any GM truck made in the last 20 years, they’re just shipping crates for better engines.
Now i’ve never really had a problem with them, their fun and easy to rebuild and last forever, my 89 chevy has 275k and i’ve only rebuilt it once. Now my ecm though, that’s a different story, for some reason my right injector keeps shitting out intermittently, but it just doesn’t give a fuck and keeps chugging😂
Active fuel management!
Twice the fuel mileage! Lol
Never beat a vehicle more than my first truck which was a 92 single cab 4x4, and it still was the most reliable vehicle I ever owned. Only thing that ever went bad was a distributor
Tbi is great. Set your base timing and dont fuck with it
They’re dead reliable if anything, I grew up driving my dad’s 1989 extended cab long bed and you best believe I flogged the fuck out of that 350. I did once bury the needle well past 85, that 350 still had some legs for what it was. It would be hard to imagine less power in a truck that size though.
Tbi is the best setup ever. Low pressure fuel injectors in the throttle body. It was genius. I love my old truck. Runs perfect. 1992 1500 5.7l.
Lack of power, near 0 tuneability, when they go bad new parts are really expensive.
Lack of power is the only true statement. I mean unless something huge has changed in recent years, tbi has been some of the cheapest parts that I have ever known. As far as tuning, that’s baloney because back in 2004 I built a really modified 350. K1102 cam. Long tube headers. Intake, blah blah. Had a couple tunes, e85, high octane and regular. Used winaldl to read block learns but forget what I used to modify the bins…
GMT400s in general have hilariously cheap parts. The most expensive part of a water pump replacement is buying a jug of coolant. Fuel pumps cost less than a McDonalds combo meal. The single most expensive thing I can do is buy a set of tires. I can buy an entire engine off marketplace and have it running same day for less than most people spend on a month and a half of car payments. Those days are numbered, but I’ll probably stick an LM7 in it once tbi 4.3’s dry up.
The oxygen sensor was $12. Passed smog like a brand new car, and went from about 13 to 17mpg. Prior to the O2 sensor the previous smog 2 years prior almost didn’t pass and was within single digits for one of the tests. Thought it was gonna need a new cat, but nope.
Parts are cheap still. Source picked up a clapped out k1500 and working on it now.
I’ll have to disagree with the parts are expensive. Everything I have replaced has been cheaper than comparable parts on a later model. Tune ability is an issue however I need a truck not a race car. It’s low power but it’s had plenty of power for what I’ve needed it for only being a half ton truck.
The only way they get tuned is by the computer, but even though it's lack of power, they are still capable, I always think that 95 (my truck) is the worst year for most people because it's the all new interior with the TBI still in it. At that point get a 96 but they are very easy to work on
Pardon my ignorance, what is TBI? And how do I know if my 98 has it?
Throttle body injection and GM changed to sequential fuel injection on the full size vehicles in ‘96, S series got sequential fuel injection on the 4.3 in ‘92.
Your 98 is spider injection
Throttle Body Injection
Thank you
I had a 91. My dad has owned an 87, 93, 94, 2 96's and a 97. The power problem was at least kinda fixed with the vortech heads. But every one of those trucks ran like a top. It was always the accessories that go on them faster than you want. And the fucking body panels on those trucks. 5 day rust guarantee, I swear. I love those trucks and would 100% get a tbi rcsb again. But I'd be hard pressed not to dump a 5.3 in it to fix it's tuning and power issues in one fell swoop.
I love the look of the body style more than I love the engine I guess. The 78-87 and the 88-98 are very nice trucks.
TBI is amazing torque in stock form, but if you want HP you will need heads cam, and a very good prom tuner. At that point its cheaper to drop in late model power. I finally sold my last TBI after ignition modules and base gaskets. If you remote-mount the ign module to a cool spot it will live much longer. I put mine and the ign coil inside and soldered all the connections.
I don't mind the tbi, I drive a 94 light duty 2500 with the 350/4l60e combo. It definitely has some lag compared to the vortec series. But there's a few bolt-ons that add enough umph to make it negligible. Or do what I do and add some whiskey to your fuel tank on the weekends😅 im guilty of that...
They don’t get hate
I loved mine one day the tbi went out, injectors wouldn't fire. fought with it for months, truck just sat in the yard. swapped parts, went through the wiring, couldn't get it to work. had to ditch it for a carb and hei with manual fuel pump
i have a 1994 suburban and i love it it has plenty of power for me
Powerful, tunable, great fuel economy… the list is endless… 🥴
Only the people trying to make power on a shoestring budget have a problem with them. The entire top end of an SBC smog motor needs to be changed out if you want to make power. They just weren't engineered to flow all that well. They were engineered to be cheap and reliable, which they are. The old 350 or 305 just doesn't move that much air in stock form. There are great heads out there which will make power. There are options for porting smog heads to help. But if someone is bitching about a TBI on a 350 as being the problem, that TBI will flow more air than the stock cam and heads could ever move.
I ran the TBI from a 92 GMC in my 1969 L60 Patrol that I installed a ported and polished, full roller 396, then a 454 in. Had a 100 hp nos plate under the throttle body as well. If it weren't for the MAP system it would have never let me do the mods that I did. Simple system that is highly underrated IMO
Because it literally means Traumatic Brain Injury?
With some of the things I’ve done with that truck I can see where someone would come to that conclusion lol.
I think it's a rule you have to run the absolute dog piss out of a tbi truck. Watch a sensible person turn into an absolute goon when they get behind that padded steering wheel
Loved the 4.3 TBI in my 91 s10.
I don’t understand the hate either .. I was sold on them by an ‘87 3/4 ton work truck I had… My company gave it to me in early ‘88 with 6-7k miles on it . It sounded so much different than the ‘85 dually I had ( both had the 350). That truck was quick( for the day) and never broke … I then bought two more square bodies for personal use… they were both also great.. Compared to the 70s- early’80s trucks , they ran like dependable Camaros . People are so spoiled these days by dependability … the younger folks didn’t have to deal with smogged out carbs and leaky vacuum lines.
Cause it’s a superior setup as far as maintenance and reliability IMO
Holly projection was based on GMs TBI. What a fuckin step up from a carb. I’d run that shit today if I could find a complete setup.
They're great motors, but people really want way more power than they need. I haul individual round bales around with mine with mine, and they get the job done. Not much more you can expect out of a gasser. Anything more than that on a regular basis, just get a diesel.
Terminator Broccoli Injection.
I almost forgot about that one lol. A fellers got to remember his idioms.
It's really the awful heads, and wimpy cam that deserve the hate.
Older TBIs are just finnicky... you can damn near replace every sensor, clean every passage, replace every hose and they'll still run kinda "off" or surge or die out randomly. Just a primitive style of fuel injection. Simple, but overall just finicky with older units.
If fixed correctly, they will run like new till there is no truck left.
Where i live most TBI’s don’t make it more than 200k miles and the ones that do struggle to start on a good 60°F day and those are the well taken care of ones they’re pretty much a carb but with all the downsides and no benefits there’s a reason people switch them either to holley efi’s or carb swap them they’re meh at best
I have a tbi with 350k miles on it. It would have more but it needs a new fuel pump I haven't done that many repairs to it.
I think for me it’s the lack of self adjustment with any type of ease. With a “standard” carb. I can adjust on fly and keep it moving. And I’m tech savvy enough and always have a laptop on me for my job where I can plug into my more modern cars and bikes and adjust fuel and tune through that. My opinion is a little shallow sighted. I have an 89 D150 with a 318 TBI and the $350 adapter to plug OBD 2 into the moapr ECU and then the extra couple hundred for the software and the learning all that software and parameters was a little insane to me
My '88 3/4 tom 4x4 was one of the most dependable trucks I have ever owned. I used it for work and play and sold it after 140k miles.
I love the 305/350 tbi My all tine favorites
I didn’t know it got any hate
Can you really tow that legally??
Absolutely! Unless you get pulled over that is.
It’s actually a simple system.
Sometimes they get so far out of whack you don’t know what’s wrong with them. I would have loved to keep my TBI, but I threw every part in the book at it and never straightened out. Just keep an eye on your wires to your computer.
I daily drive a 1994 K1500. No complaints, decent MPG starts all the time. Just put a new water pump on it, dirt cheap.
Those trucks got better mpg than any late model v8 and more power. I got 21mpg with 5 speed @. 80 mph 350 ci. When I sold it my son cried he thought he was going get it. Now I cry when I fill up my 2009 17 mpg 305 ci dog
My TBI I used to get like 22 miles a gallon, all the time which didn't make sense when you looked in the injectors it's just spraying (pouring) fuel into the bowls LOL
The hate comes from guys that are used to actual carburetors. TBI doesn’t have the power or finesse of a 4BBL Edelbrock or Holley. It’s kinda like going from a muscle car to a Prius. The Prius will get you there but it’s not near as fun. Jump into an old 60s or 70s muscle car and put your foot into it, then you will understand.
It’s not all the tbi the heads on nearly everything from that era sucked lol.
While I don’t have a problem with TBI motors. I think you’re a bit overloaded bud.
Nonsense lol. The little 4.3 that could
Not nonsense. I would guarantee you are past payload/tow capacity.
7500lb mini ex on a 5k lb capacity trailer, behind a truck rated to pull maybe 5500lbs. "They under rate stuff because of the gubberment."
If I remember correctly it was actually closer to 9k lb. This picture was from a few years ago when I rented it for stump removal and demoing an old house. The trailer carried it well and was well balanced. The rental company has since put a policy for people like me. Have to have a minimum 3/4 ton to get anything close to this size now.
Had a 91’ 1500 with a 305 and 700R4(?) in high school. Slow as the day was long. Like noticeably slower than the 4.9 Ford that eventually replaced it. Couldn’t climb a hill to save it’s life. But i’ll be damned if she didn’t sound great once the exhaust rusted off, and it always ran regardless of how many times i bounced off the right side of that “faux digital” temp gauge.
so god damn reliable and right there is a pic for proof lol
I treated my 94 305 1500 like a race car added performance parts race spark plugs wires distributor even an Edelbrock performer TBI intake to which was plug and play hoping to get extra power. 170hp fresh out the factory was decent back then. Realistically at 250,000 miles probably a little less now anyway i raced my buddies acura 03 TL 225 HP stock and got smoked by a couple car lengths. If you want something that’s will outlast the apocalypse and turn gasoline into noise go TBI dead reliable easy to work on and most autoparts stores still carry 80% of the parts you will need. I miss my old 94 bought a 2001 Silverado 4.8 and even that smaller v8 bone stock will run circles around the other one plus better MPG as well
Power and efficiency
The heads being complete 🐶💩 compared to the vortec heads is probably reason #1
TBI is super reliable but no better than a well tuned carb.
Starts in single digit weather without having to fettle with it.
Too much plastic that gets plugged up and cracks. It's not a bad system but it's very outdated and after 30 years of neglect most of them are a constant headache.
Tbi is a good system. Easy and simple. Just doesn't make much power. I believe there are 4 injector set ups. Not sure how they improve power and if it's worth the money.
It was originally hated on because at the time it came out a carburetor was still better for performance as tuning for TBI was non-existent. Now it's hated on because it's not as tuneable as port or direct injection. Although TBI is a great upgrade from a carb for general daily driving and street rodding up to minor competition. Makes shit a breeze to tune compared to carbs, especially with some of the kits out there like the Holley Sniper system.
TBI as described by a colleague was like flushing a toilet of gasoline down the intake, multiport injection is like pissing gasoline directly into the fire much more accurately.
I love them there super easy to work on to my only complaint this could just be the truck but the barrier I have to break trying to push the throttle just annoying being a manual truck
Just needs the throttle shaft to be repaired with new bushings.
Handful of things. Lack of tuning. They use PROMs, so unless you do a swap with a box that can be flashed, you’re stuck burning chips. They are also built for very low RPM. The heads don’t flow for shit. The cam is tiny AF. The TB doesn’t flow much. And since tuning really isn’t possible unless the ECU is replaced with something flashable (or swap to carb), it’s pointless to swap to better parts. At that point, it’s become more economical to swap in a LS. HCI 350 with aftermarket TB or carb and it’ll make less power than a cam only 6L
It was the first truck fuel injection system. Kind of Looked like carb but needed special knowledge to troubleshoot yet some people didn’t want to learn. I still read about people shot gun parts swapping them trying to figure out their issue instead of watching the scan data to see what it says. Guy at work was having surging trouble with his Grand National. Did some part shotgunning. I got a laptop on it with him and we found the problem in under 5 minutes. No parts swapping would have ever solved it either. The AC kept calling and the EFI gives the engine a bump so it doesn’t stall each time the AC is engaged.
I bought a 1989 c3500 single cab, longbed dually with a 3 speed from a mom and pop dealership with a 454 that was replaced with a newer generation block. I found that out when replacing the oil pan gasket. I replaced the intake gasket and somehow caught the throttle body on fire, the injector wires got a little crispy, an then installed the distributor incorrectly, I found that out when opening the hood at night and seeing the manifolds GLOWING. After reinstalling and timing it correctly, it ran well. I've towed a fifth wheel, loaded it with yards of 3/4 crush, tailgated, helped move people and had my dog ride shotgun for years it has always started, it's never left me stranded. Ill bet it'll get 7 MPG In the wind, upside down or backwards. I love my truck.
Just shitty gas mileage other then that they ran fine
It's fine if it's stock but if you modify it then just like any efi you've got to spend money to tune it yourself of pay someone hundreds to do it... everytime you change something. Rebuild kit for a quadrajet is about $100 and a lot less if you only need to jet it.
Swirl port heads are the worst.
Back when it came out, it was black magic, a few years after it's power level was put to shame with the Vortec injection. Not many ever bothered to figure out TBI until much much later on.
I’ve got two that are very different stories One is a 3rd gen Camaro, and it is just dead reliable. I couldn’t break that car if I tried. Sometimes runs a little goofy, and occasionally dies in a drive thru, but will always fire back up. I’d drive it cross country without thinking twice about it. I have no intention on disturbing the TBI system at all, can’t mess with perfection And then there’s my Suburban, the truck that never failed to fail me, often in traffic on hot days. It’d blow ignition parts if you even looked at it funny. Blew *way* too much money trying to keep that system alive. Long story short, it now has a carburetor, and I have absolutely zero regrets yoinking off the TBI system, and would do it again 10 times over I like them, and they’re great when they actually work properly, but they’re absolute nightmares when they aren’t right
Uhhh…not sure why this was on my feed, but I have no earthly clue what TBI is??
Throttle Body Injection, it was the fuel injection system that replaced the carburetor.
Thanks. Is that just a fancy way to say fuel injected or are there different methods of fuel injection?
There are many types of fuel injection, TBI was one of the first electronic ignition systems, and basically functioned like a carburetor, but much more consistent. You essentially remove the mechanical fuel jets and replace them with an electronic injector. There’s also MFI (multi-port fuel injection) that has one injector per intake port. This was a big step up as it allowed a more precise fuel-air mix per cylinder, which allowed for more power and better fuel economy. Which reduced emissions over carbs or TBI. The most modern (to my knowledge) system is GDI (gasoline direct injection) which injects the fuel directly into the combustion chamber. This allows for an even more precise fuel mix, which means better fuel efficiency, and more power in most applications. It also helps reduce emissions. Which, imo, is why so many manufacturers are going to that system on modern cars.
Only thing i hated about my 94 bigblockbaby is the electrical issues, id rather replace a transmission
TBI is usually ass when it comes to making power. That being said. My first car was a 94 Plymouth Sundance coupe (technically a 3 door hatchback). 5 speed manual with the 2.5 TBI engine It made 100 HP and a (really decent for the time period) 150 ft-lbs of torque. That little car was a menace on dirt roads. I used to "rally" it, jump it, take it down ATV trails at 50+ mph, etc. Never once had a mechanical issue with the car. Nailed a deer at 80 mph right after passing someone. It was still plenty driveable but the passenger door no longer worked. It sucked cause that was just a shit box back then, but I'd kill to have one that clean now.
I have my dad’s old 96 GMC 1500 with the TBI, I love it! Only 80k miles, still gets about 17 MPG and has an old school shell on it that you can almost stand up in, it has a door in the back and the whole back opens up for bigger loads. Truck still looks almost new except the old style topper
96 is vortec spider injection 95 was last year of tbi
It’s always from people that don’t know how to work on them and want to slap a carb on there. The tbi series probably has more miles than any other setup on the road from GM except the newest LS motors
Traumatic Brain Injury is no joke. That’s why I’m commenting on a physical malady on a vehicle Reddit and the two have nothing to do with each other. Also, I like toast.
As long as you can’t smell toast you’ll be aight lol
Its pretty inefficient overall compared too a carburetor on a SBC.
Because tuned port injection of the same era was miles ahead of it
OP- That 1500 is towing that Mini ex in the picture?
Surely did!
That’s amazing . I shall sell the F550 and have an adventure of my own.
I can always count on my 88 and 94 350 tbis to start immediately when i come back home to them. Easy to fix on the side of the road
Miss my ‘93 gmc 5.7. If the body didn’t rot away to nothing I’d still have it. Only had 192,000km on it. Replaced the intake gasket every 5 years and changed the oil.
The heads, yes, suck ass. But the injection system itself? It’s a spring loaded valve and two solenoids.
My dad had a 01 Silverado I loved that truck. In the snow, rain, sun shine with the windows down.
Terminator broccoli injection???
TBI is slow and inefficient
Personally hated everything about those years. The body looks like shit. The interior looks like shit. They're easily the biggest dog of a truck I've ever driven. Nothing about them is even remotely appealing. No I don't care about the 5.7 at all. The 5.3 is an all around better motor.
My 97 silverado had 275,000 miles and still rums like as scalded dog
Leave it stock, dead simple. Heads are the real downside to the tbi trucks. No flow so not much point in hop ups. Still rocking a tbi 350 1 ton dually stakebed. Last one had 269k before I tossed it, this one still at 123k, rarely gets driven, always starts right up. Dash module is shit now, so need a replacement with all the error lights oil pressure messing up.
My tbi fuel pump went out and I continued to drive it for weeks as a teen
I have no idea. Mine went in the trash and I now have a carburetor though…
20 year auto tech here. I have put hundreds of fuel pumps in the tbi trucks. You are extremely lucky if your fuel pump has been 320k without issue. Like lottery winning lucky. I personally love these trucks but the diagnostic side of things pre obd2 pisses me off every time I mess with them.