Chevy 350 tbi stumbles on acceleration. Hopefully a kit will fix that.
Chevy 350 tbi stumbles on acceleration. I've seen multiple times the ICM (Ignition Control Module) will wig out once the engine warms up after a while (don't use Chinese junk parts). 14° idle and 35° at 3000 rpm. Jul 5, 2012 · Cure The Bog And Sluggish Response On Your Holley Four-Barrel Carburetor, By Properly Adjusting The Accelerator Pump Assembly. Bad spark plugs are one of the leading causes of a lack of acceleration in Chevy vehicles. I need advice on carb settings. i also just put in a new coolant temp sensor and rebuilt the TBI. Aug 12, 2019 · It s/b 9 - 13 PSI (according to GM specs), at idle and under acceleration, preferably 11 - 13PSI. 52 X 3. 7L TBI Here's a list of what I've done so far. Unless I accelerate very slowly, it coughs and stumbles and wants to die. Timing at 12. Seems to be less hesitation when engine is not fully warmed up first thing in the morning. Apr 28, 2008 · I am anxious to hear what you find here, I am chasing the same problem. I got this hesitation while accelerating that has got me stumped, its been doing this for almost a year now, and trying to fix it. Does not do it with the timing wire un hooked under the dash when driving or parked. It starts and idles with no issues. It has had cylinder 7 misfire, random misfire, rich, and 02 Jul 23, 2002 · My engine hesitates on acceleration from stops and also on slow to moderate acceleration. And the truck seems to be low on power when at wide open throttle even when warm doesn't Nov 24, 2014 · Okay I will try to get all the info in one shot. This can cause the pump to lose power and stall the engine. I replaced the fuel pump-because it was bad in July. No problem most of the time, and if I accelerate slowly, it runs perfectly, smooth as silk. 7 tbi. 7L 350, TBI, Auto, 220Kmiles Its been a great truck, for the most part it runs and drives great! but at low idle or low rpm's it missis,sputters,surges and if im just barely giving it any gas it almost wants to stall out. Mar 21, 2021 · My 1995 Chevy 350 stumbles when I take off from a stop. When driving it shudders erratically at idle when in gear (ie: at a stoplight). Nov 24, 2010 · I have a 91 Silverado K1500 4x4, 5. Connected it at the back of the TBI and then again before the fuel filter; same results from both locations. With key on, ZERO fuel pressure. It's almost like a hiccup. Even slow acceleration is no longer a guaranteed thing. I ran a datalog with WinALDL and the only thing that stood out to me were a bunch of rich flags. 73 gear would accelerate much faster 2. When a spark plug goes bad it can cause cylinder misfires, rough idling, and acceleration issues. - New fuel pump and fuel filter. Jul 28, 2021 · Most Chevy’s have a spark plug replacement interval of 60,000 to 80,000 miles. Guys my dad and I are desperate for help. Partially clogged injectors and a small vacuum leak. Does not do it in park. For the past 8 months now it has been running poorly. Jun 20, 2006 · The leak was small enough that it would not stumble/surge under regular acceleration but with powerbraking or feather light throttle it became very apparent. I let the truck sit with gauge on Feb 19, 2018 · 350 TBI: Scanner Shows Knocking on Acceleration. When I try to accelerate when it is cold it stumbles and shakes the truck like it is starving for fuel but doesn't die. Sep 22, 2011 · i have a 1995 chevy k 1500 350 tbi it hesitates when trying to accelerate changed plugs wires cap and rotor it dose - Chevrolet 1995 K1500 question Search Fixya Press enter to search. but it runs great when accelerating or about 60mph and faster almost like nothing is wrong with it. 7L TBI intermittently stumbles/stalls at idle, and frequently falls flat on acceleration down the road. Jun 24, 2022 · If your Chevy 350 TBI stumbles on acceleration, it may be due to a defective fuel pump relay. 89 TBI 350 Rough Surging This morning the truck drove great with only a few light stumbles, on light acceleration, as I went to church. For good acceleration you want a 1st gear X rear axle ratio of close to 10. I’ve already changed the tps, Iac, O2, egr valve May 18, 2022 · An air filter or screen plays a vital role to keep the engine cool and maximize the engine performance. Feb 11, 2016 · 1988 chevy k1500 TBI 350. I have a 97 Suburban 5. Clogged fuel filters or a failing fuel pump can cause the engine to bog down. See full list on thegrumpymechanic. It does have allot of miles on it (275,000) but for the most part it runs like a clock. - Replaced the TBI base gasket. Will barely accelerate under load because of this. 5" Pv 89 jets rear and 31# squirter MSD Streetfire Hei distributor. May 30, 2022 · On my truck, (91 Chevy k1500 l, 350, TBI, not cat, no EGR) if I drive it when it's a little cold, at about 2-3000 rpm, it has a slight hesitation. It has no power when it does this. But when put back in neautral or park and revved out, it will smooth back out. I've done a little digging on these forums and found an entire laundry list of what might be the problem. On hard acceleration it is bogging down like there is to much air, because sometimes it backfires. It seems to have slowly gotten worse over the last six months. Oct 5, 2007 · Guys, I'm stumped here, HELP! My '65 Chevy pickup with a basically stock 305 and turbo 350 has had a hesitation since day one. Sometimes it is no big thing, sometimes pressure/volume problems arise. Assuming the hesitation is annoyingly still present, now we can turn our attention to the carburetor and accelerator pump. Failed Ignition Coils Apr 21, 2022 · Remove the carburetor from the engine. I still have one small issue. Replaced distributor components. I have exhaust backfire when I have heavy acceleration. Accelerating under load it sounds like a helicopter and is low on power (missing?). Idling in N or P it only stumbles occasionally, but when in D or R it stumbles pretty badly, rpms seem low (like 300) and fluctuate by 100rpm or so. '89 Chevy 1/2 ton 350/auto TBI; Surges at idle, stumbles on acceleration (worse when cold), and starter spins waaay too long before engine starts. Oct 7, 2013 · Your combo has a very "tall" gear for acceleration. With the pump all the way down, lift it up to the top of the pump well. old_silverado; Jun 4, 2024; Engine Performance + Maintenance; 350 tbi stumbles on acceleration and low on power. 3 I'm annoyed with the hesitation when I try to accelerate quickly. Apr 19, 2014 · Re: Chevy TBI 350 stumbles on acceleration « Reply #9 on: April 19, 2014, 12:09:50 PM » so the 2 black wires, do you know what there were connected to on at least one end? Jun 2, 2008 · Howdy - My father in law's '91 Chevy was running poorly, so we put new plugs, wires, cap and rotor on it, and it's running better, but it it still surging at idle. The wiring, and screen with the pump, in the tank. 7, 2wd. 52 M22 trans with a 3. And with that the Fuel Filter. Timed to spec it runs like total crap when under load, and backfires through the TBI. The engine hesitates and sort of coughs causing the truck to lurch and doesn't run smoothly but at higher rpm it seems to run well. Used to be hard acceleration would cause these symptoms but an easy acceleration wouldn’t. The issue is that times it feels like it doesn’t have the go it should have and it goes in and out on that like sometimes it’ll run great and then it’s falls on it’s face. It stumbles and backfires when accelerating. com Apr 9, 2024 · I have a 87 Chevy 350 that was running good but latley it has been stumbling and backfiring when you step on the throttle heavy. Oct 19, 2017 · 95 GMC TBI 350 accelerating problems Jump to Latest 23K views 22 replies 7 participants last post by Zach Smith Nov 16, 2017 Mar 25, 2016 · The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1973 - 1987 Chevrolet & GMC Squarebody Pickups Message Board: 87 TBI 350 runs rich, stalls, stumbles, slight backfire out exhaust Nov 28, 2011 · 350 chevy - bored . Sep 21, 2013 · Acceleration from a stop is very poor. Just replaced injector that wasnt spraying well and was leaking on top. I tried setting my timing at 35,34,33 total timing at 3,000 rpm and still have the problem then i tried base timing at 8 and 10 btdc and lower, the engine ran bad. Has a quadrajet carb, new fuel pump and filter, new points, condensor, new coil. It's a 89 k1500 5. Yes, I know, that makes the engine a wild unknown. If your Chevy has a Mass Air Flow sensor, a gummed-up air filter by dirt & debris will reduce the amount of air entering the intake. When you drive with the clogged air filter, 350 TBI hesitation when accelerating is something you will Common issues that can occur in vehicles using a throttle body injection (TBI) system include idle surge and stumble. This kind of fuel injection system uses a single injector housed in the throttle body to provide fuel to the engine. Aug 3, 2024 · 1994 chevy suburban c1500. Only when cold. New with Taylor spiro pro wires. 2 X 3. Timed by ear it runs best with advanced timing, but starts hard hot or cold, runs terribly cold, and occasionally backfires though the exhaust when under load. Apr 8, 2022 · Hey there, I’ve recently been experiencing a lot of hesitation with my truck. Changed the distrubutor cap, rotor button, fuel filter and in-tank (holy Oct 3, 2011 · My 350 with an Edelbrock Performer has been great from the start. 7 V8, 4L80E. 08 gears with a 28" tall rear tires and a 2. New wires and spark plugs. 776. If your car or truck is equipped with a Holley four barrel carburetor and stumbles upon acceleration, more than likely the carburetor needs an adjustment to the accelerator pump assembly. Feb 20, 2018 · 1967 chevelle malibu 427/700r4 1971 cheyenne 10 350/350 1983 gmc k3500 454/400/205 1987 r10 tbi 350/700r4 2014 cruze 2. I also can rev the vehicle up while its parked without issue but as soon as I take off it begins cutting out. Aug 18, 2022 · If your Chevy 350 TBI bogs down on acceleration, there are a few potential causes that you should check. I changed the fuel filter and the injectors look fine. . It will loose power when at speed and when accelerating. 1989 Chevy Suburban V Apr 9, 2010 · My 350 TBI in my truck is becoming undriveable with a really bad bog and hesitation/stumble when I try and take off at any rpm or speed. 08 = 6. 73 = 9. New plugs and wires. It's pretty much always there, I can get it to behave a bit once I'm moving but that's really only between 20 and 40 mph and that's by hitting the sweet spots. Is there ANYTHING else that could be causing this? Burb is 91 w/ TBI 350 and 4L80E. The "missing" with the carb off the 350 is only noticeable under hard acceleration. It will not idle right when in drive, but in park it is better. Hopefully a kit will fix that. First, make sure that the fuel delivery system is working properly. but she still stumbles and stalls when warming up dosent do it when cold or fully warmed up also only does this when under moderate to heavy acceleration and backfires too. Feb 22, 2010 · The carb that was on the '70 had a real bad flat spot. They didn't see anything but suspected a bad ECU, so I sent in the whole thing in and they rebuilt it for free (kudos Holley). Customer: My 1995 Chevy k1500 Silverado 350 V8 stumbles and hesitates when i take off from a stop, it idles fine and runs fine after its moving but off the line it seems like it almost wants to stall. 350, 600 Edelbrock, Standard dist with Petronics HEI module. 2002 Chevy Tahoe LT 4WD 1997 Chevy Tahoe with 2002 Tahoe front swap bagged on 22s ///RA TENNESSEE CHAPTER. Turns out there are two very common and easily correctable problems with tbi motors. it hesitates, misses, stumbles, at an idle and under acceleration. 05-08-10 05:02 AM - Post# 1911682 I have a 89 chevy 1500 with a 350 tbi, i just put new spark plugs, wires, cap and rotor and replaced the coil. Mar 10, 2017 · Let’s say your initial is 14 degrees with 21 degrees of advance for a total of 35 degrees BTDC. The EGR acted normal at idle, I could lift the pintel off the seat and it would induce a leak and cause the engine to miss/run rough like you would expect. I have a mild Gen I 350 with the Holley 300-36 high rise dual plane intake and the same 670 Avenger, new carb, same miserable hesitation. But as soon as it put back into drive it stumbles again. First, the fuel pumps are extremely picky and prone to fail if run out of fuel. Hello I'm a new member. No codes were set (other than 12). Jul 29, 2007 · OK I am almost finished with the project. The motor seems very weak to me vs what it should be. Nov 22, 2008 · 1995 350 TBI Hesitation when giving gas. It's OK at steady speed, but not great. May 20, 2010 · It's common when putting headers and or duals on these TBI engines to see the EGR failure code illuminate because the reduced back pressure doesn't feed enough exhaust through the valve to heat it up to the expected temperature. I checked the timing and is spot on from when I put the motor in, I painted the marks. I got a 1990 Cheyenne with TBI 350. I currently have a mallory unilite distributor . Tanks INC EFI fuel tank and pump. Once I speed up, it runs fine again. Oct 8, 2018 · It had a stumble under load and I had a heck of a time finding the cause. If you accelerate gently, not too noticable, but when you accelerate hard, it hesitates pretty badly. Have adjusted my timing for 14 initial and 36 total. You should have the relay checked by a qualified mechanic as soon as possible to prevent further damage to your engine. Save Share May 15, 2017 · I have a 1994 sbrc 2wd 5. It revs up fine in park and low acceleration but doesn’t like to accelerate when you step into it a bit. Jul 19, 2009 · The engine is a 1969 350 chevy. Its really bad on the 1-2 shift. 96 Chevy Silverado, 5 Customer: I have a 1995 Chevy K1500, 5. All 4 years old with less than 1000 miles. It starts and idles fine, but cold or warm, it hesitates under acceleration. I rebuilt the fuel pressure regulator on the TBI, problem still there. 69 Jets front 6. 030 over stock rebuild with a Rochester 2GV carb and HEI distributor. Take the top off of the carburetor. 7 TBI motor. It’s a 1994 gmc c1500 with the 5. chevyprostreet; Customer: 1993 Chevy K1500 5. We tried a known good quadrajet off another car that was running fine and it still did the same. Problem is engine starts and idles fine but as soon as you give it gas it dies everytime. Has a new 1906 Edelbrock carburetor. Jul 10, 2014 · I have been going round and round on this truck with no final fix. Here is what I have done so far: - Sent data log to Holley. I've already replaced the fuel pump, the problem is still there. After letting my 1996 Chevrolet 1500 work truck with 5. I've "looked" for vacuum leaks but came up with nothing but I still need to try the propane torch idea. Apr 20, 2014 · Re: Chevy TBI 350 stumbles on acceleration « Reply #21 on: April 20, 2014, 06:50:41 PM » As long as the base timing is between TDC and 6° BTDC, and the engine doesn't ping, timing isn't likely an issue. You would hit the throttle and it would sputter and then go. May 22, 2021 · Seems alot worse when wet weather. I don't know if this has anything to do with it but it seems to crank over a few to many times on start up than it used to i would appreciate Mar 21, 2012 · My 98 350 vortec, 4l60e with 115k miles,falls flat on its face on acceleration. My 91 TBI 350 Jimmy hesitates on hard acceleration. Of course worse under acceleration, slight at idle. Oct 29, 2009 · hesitation on hard acceleration. Or a plugged exhaust. I have a 1997 Chevy 1500 5. Fill the float bowl with a fluid like mineral spirits. Jul 24, 2013 · New to the forum with (maybe) an old problem. 030" over 11:1 compression L98 Aluminum heads 58cc Edelbrock Streetmaster intake. The previous owner had a friend build him the engine when he totally rebuilt the old girl from the frame up. 68 Coupe, 350 w/ Edelbrock Performer RPM heads, cam, intake, 700R4, Dave's small body HEI Bought my first big-block Chevy in Oct 3, 2023 · I can’t seem to find the root cause for a sputter on acceleration in my 350. Dec 6, 2022 · 2008 Silverado 5. 350 tbi stumbles on acceleration and low on power. 3. The engine is a Chevy 350 with a Holley that is not the original engine or carb in my Chevy. His 350TBI stumbles terribly upon acceleration. System is going lean, and after 20-30 seconds of running lean, then goes into open loop forever. Nov 3, 2018 · 88 350 TBI stumbles in gear when hot. 7L vortec v-8 and 4L60e trans (203K on the engine, recent rebuild on trans) sit in the driveway for a couple weeks, I hopped in to head to the parts store. Jan 2, 2012 · My truck (in sig) just developed a bad stumble on acceleration. I had two problems at once. It will sputter, then regain acceleration. Wires are correct. Now, doesn't May 1, 2020 · Chevy 350 w/ MSD ignition Street Fire CDI. You have 2. Also while driving down the road it'll cut in and out for a few seconds. This would be a great combination. I put in a new cap /rotor, Spark plugs today. With the timing set, now you can see if the acceleration hesitation is still present. When it gets to operating temperature and the idle drops more it is more noticeable. it just started a couple days ago. Any ideas what causes the hesitation? It is a stock 1988 TBI 350 with low mileage. Not all the time, but occasionally, and then after maybe a minute or so it just goes away. Engine is a . I have tried several different base timing settingsbest I have found is with no vacuum about 25 base and 45 all in by 1800 rpms. chevyprostreet; Aug 3, 2024; Engine Performance + Maintenance; Jun 22, 2023 · I have a situation re: carb stumble and backfire under acceleration. 7. Vacuum advance. 0 turbo diesel Aug 9, 2012 · I have a 1994 GMC Sierra 4x4 with the 5. Low rise single plane Holley Truck avenger 670 cfm carb. At idle I'm getting 52 psi, with the key on and not running the psI is at 58. I replaced the fuel pump and it seemed to remedy the problem considerably however Sep 29, 2010 · sbc pinging I have a pinging problem in my 350/400 hp sbc. Jun 20, 2020 · At slow speeds and under load the oil pressure drops to 5ish and stalls out. Jun 16, 2020 · I have a 1995 c1500 with a 350 tbi in it. I put a fuel pressure gauge on it. A 2. It idles fine, drives fine. 7 tbi 4l60e. Feb 6, 2009 · Please help me diagnose this problem. When I take off in the morning for school it loves to stall on me and for some reason my “check gauges” light turns on when it does. 2 first gear = slow acceleration. Easy to replace, any junkyard with chevy/gmc trucks has a dozen Dec 19, 2003 · Fairly inconsistently while accelerating it will start sputtering, hesitating, misfiring and any other way an engine could run bad. The TBI and engine are stock. Recently, I began having very bad surging (not all the time) when I try accelerating from 35mph (or more) up to highway speed. Full throttle acceleration is strong and good. 4 My gauge is mounted permanently to back if the TBI, my question is could the heat of the engine affect the reading on my gauge? So I still have the slight hesitation upon hard acceleration and then it seems to catch up and run fine. i started adjusting the allan key adjustment in the vacum advance canister counter clock wise to reduce the advance curve Aug 26, 2009 · I just fought this demon with my 93 Blazer. The engine throws black smoke on startup. I bought a fuel pressure test gauge. Pushing the throttle at this point causes the engine to stumble slightly before it revs up. emd bpp tytumvg aauatpbo ccqb tjikt ksbzt diiq xtv miriv