350 tbi surging. Not all the time but most, usually after it's warmed up.

350 tbi surging. Im wondering if somehow the base idle got messed up somehow. Every question thought and help is greatly Apr 14, 2024 · Valdfur V 9 350 TBI surging idle 91SilveradoZ71 Jan 23, 2025 Engine Performance + Maintenance Replies 5 Views 3K Jul 10, 2025 Jun 4, 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. Its runs pretty good after it warms up but the idle is high at that time. I just can't nail down the problem. Did tune up, plugs, wires, cap, rotor, ignition module, o2 sensor. Any ideas? Engine & Drivetrain Nov 15, 2021 · Similar threads 9 350 TBI surging idle 91SilveradoZ71 Jan 23, 2025 Engine Performance + Maintenance Replies 5 Views 3K Jul 10, 2025 Aug 26, 2009 · i have a tbi 350 out of a 90 suburban in my jeep. 88 Suburban TBI 350. Inspect the throttle body gasket for vacuum leaks causing erratic airflow. 1. If I unplugged that tan wire w/black stripe, it wouldn't die. All started about a week or so into really cold temps, not sure if that could have anything Jan 18, 2010 · I have a 91 Chevy 350 TBI in my truck. And you seem to have plenty of power when Sep 10, 2019 · 9 350 TBI surging idle 91SilveradoZ71 Jan 23, 2025 Engine Performance + Maintenance Replies 4 Views 1K Feb 8, 2025 SAR K2500 Burb S Running rough problem stevenharris27 Nov 12, 2024 Engine Performance + Maintenance 2 Replies 15 Views 2K Nov 18, 2024 vanderdude V C Engine Wimpy, MPG Insanity CrashDriver Dec 28, 2024 Engine Performance Feb 11, 2019 · Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members. The truck has a NV3500 so the whole truck would surge. One out of five times the idle will seem to fall out when taking it out of gear and coming to a stop. Jan 12, 2008 · Hey all. Im having surge problems at idle. Truck runs good when given throttle but the surging and stalling is driving me crazy I’ve tried everything. I have a knock count even at idle with the timing at 0 degrees. It started surging under acceleration in 1st and 2nd- woom-woom-woom-wooo! Felt like it was going rich-to-lean very slowly. It runs great never hesitates or dies it will idle high at the stop light and then go to low idle but surges. When I step on the gas a bit it will run but idle really rough. Also I disconnect the negative Cable from the Battery and it dies. They said to spray carb cleaner around the base of the TBI and see if the engine speeds up. The fuel pump in the fuel tank had a deteriorating rubber hose between the pump and the fuel supply line. Apr 17, 2021 · Jul 10, 2025 DerekTheGreat K 350 TBI ran fine, now surging start Kleavitt18 Jan 3, 2025 Engine Performance + Maintenance 2 Replies 15 Views 2K Jan 6, 2025 New member here looking for some help with 350 TBI running richUnfortunately you have dreaded tbi surge. Already checked/changed Did a compression test, all cylinders and they were consistent at 190psi. It revs up fine in park and low acceleration but doesn’t like to accelerate when you step into it a bit I’ve change plugs, distributor rotors, distributor cap, esc Jul 20, 2018 · Chevy Forums FREE technical assistance for your restoration and repair. Coming home, it had a rough, surging idle on startup, and a lot of stumbles all Jan 13, 2022 · 1994 Chevy c1500 5. This was quite bothersome descending hills in low range/first. in the morning the car used to start on the first turn of the switch, but now it takes Nov 3, 2018 · I really need help, this is my only vehicle, and I have to get to work every day. It was a fresh build 4 years ago and has maybe 5k on it. Runs good but after warmup at idle it surges probably 300-500 rpm. Some other symptoms to look out for to ensure that the problem is indeed a vacuum leak are hissing sound from the engine bay, stalling while stopping, etc. I thought no big deal its a good deal I'll figure it out (lol) Jul 7, 2024 · I have a Chevy 350 that keeps surging and stalling it’s a 1994 with tbi i notice when it surges and I add a spray of starting fluid it starts to run normal. I also did the ultimate tbi mods, turned up the fuel pressure to 15 psi and used a tbi intake without all the smog stuff. Can't see any leaks around the injectors with the key on Chevy Forums FREE technical assistance for your restoration and repair. Truck has dual exhaust no cats. Dragged the CJ-7 up to Northern California and ran the Rubicon last week. I don’t know if that points to one certain thing or if I still at the point of “replace every sensor and hopefully it’ll fix it”. New MAP sensor New IAC New TPS Replaced all fuel lines, new pump, rebuilt throttle body (with gaskets) new Apr 4, 2022 · Howdy, So I recently bought an 87' GMC SIERRA short box with the 350 TBI and When I start it, it surges bad and trys to die, and then begins to idle better but still not right it sounds like a misfire. It's always when I'm half throttle at cruising speeds it will surge 2-300 rpms and it's annoying as fuck. It will correct itself after about 5 seconds, can usually correct it a little quicker by revving. it idles rough and acts like its running really rich, then when you take it out to drive it, as soon as you step on it to put a load on, it cuts out and backfires. Temp sensor, map, and tps all appear functional, checked with scan tool. 7L rebuild with a new Jegs TBI, new high-pressure fuel pump and cold air induction. You could be in a situation where the gasket seals a little better when warm. I've messed with the engine timing, compresson tested it, all new electronics and it Apr 3, 2023 · 350 Tbi rough idle overfueling rough idle tbi Jump to Latest 3. Takes longer to… Jun 15, 2021 · Yes, TBI really isn't designed to have idle monkeyed with. It's been a while, but I'm back with my 89 Suburban. Cap & Rotor & Fuel Filter. ) I think i got a fuel issue Jun 5, 2008 · Its the factory 350 bored 60 over with 98 vortec heads a slight came upgrade and stock TBI. I has so far Feb 26, 2017 · Hello guys I'm new to the forum but I've been visiting it regularly since I've bought this truck. They symptoms: 1) The idle surges after a cold or cool start. 0L AT. Truck ran fine before rebuild, aside from at end of life due to age. It idles fine while you're sitting at a light or something like that in drive, but the minute you put it into Park, it surges pretty badly. Since unplugging the EGR vacuum line stops surging, inspect the EGR valve diaphragm and vacuum hoses for cracks or leaks. New MAP, EGR, O2, TPS, ESC, distributor and coil. I have to crank the motor for around 10-15 seconds it will try to start. I replaced and tested the Engine coolant temp sensor New EGR and solenoid. Basically, it doesn’t matter if it’s in gear or in park, after maybe 5-10 minutes of driving once it gets good and warmed up, if you go past barely 25% throttle all it does is surge at 2500 rpm, but if you baby the pedal it does fine. thanks for any help 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. He says he can mess with the EGR valve by manually moving it and then it will idle correctly. Problem: excessive corrosion internally on the Engine Coolant Temperature Sens Oct 14, 2023 · I had the problem you are describing in my 1994 Full Size Blazer with the same 5. Sometimes it surges forward than dies, after a restart it will idle smooth for a bit. Inspect all vacuum lines for cracks or disconnections, as these affect air-fuel mixture. Got timing roughly set around 0. 7 350 TBI often faces idle surging and stalling after warming up, linked to fuel delivery or sensor faults. It's pretty much Jan 17, 2022 · So I replaced the icm, map, egr solenoid, with acdelco parts. I have a surging idle but only in Park. Has ran rough for several years. idk what the issue could be PLEASE HELP Feb 15, 2016 · I have been pulling what hair I have left out over this issue. Also went to the treasure yard and found a much lower mile tbi 350 and I pulled off the tbi unit. Did compression test and all are 168-176. Jun 5, 2005 · Howdy! My son used to have a 90 Camero with a 350-tbi. My experience with pumps is they are fine or dead. 2K views 17 replies 5 participants last post by NorCalJalopy Jun 18, 2023 I have a 95 GMC 2500, TBI 350 with 252,000 miles, and I’m having a surging issue. RPM surging in a 1988 Chevy TBI 350 can stem from vacuum leaks, faulty idle air control (IAC) valve, or dirty throttle body. I have looked and looked Apr 10, 2013 · TBI issues-surging idle The 1973 - 1987 Chevrolet & GMC Squarebody Pickups Message Board Oct 12, 2023 · Got a new pcv valve because they’re super cheap, replaced the line from the intake to the valve, replaced the line from the egr valve to the intake. ) I think i got a fuel issue Nov 6, 2014 · 87 Chevy 350 TBI low Idle issue The 1973 - 1987 Chevrolet & GMC Squarebody Pickups Message Board Jun 25, 2020 · Jun 9, 2025 Bill USN-1 D 87 tbi 350 popping at idle and running rich devildogcummins Jan 15, 2025 Engine & Performance 2 3 4 Replies 48 Views 5K Mar 10, 2025 Apr 28, 2024 · I am trying to diagnose a surging idle and stall condition on a 1990 GMC S15 Jimmy with 4. It goes away after I drive it for a minute or it warms up to closed loop. It does have headers and no cats. Jul 8, 2024 · Anybody know why my 350 tbi could be surging 350 tbi engine surging issue discussion with possible causes and solutions Jan 14, 2018 · I rebuilt a 350 TPI with iron heads from a 89 Camaro. I replaced IAC, CTS, TPS, ETS, EGR valve, EGR solenoid, FPR, Injectors TBI being a MAP sensor based system will see the leak just like opening the throttle blades and will feed the leak and then you have a high idle. 7 TBI. It feels like a misfire. Jan 22, 2017 · My 93 350 TBI has a strange high idle problem I can't figure out. I can't find any sensors that seem bad. My truck runs great but it didn't right after the swap. Jun 24, 2024 · Sep 3, 2025 PlayingWithTBI 9 350 TBI surging idle 91SilveradoZ71 Jan 23, 2025 Engine Performance + Maintenance Replies 5 Views 3K Jul 10, 2025 Surging at low and steady speeds in a 1995 G20 with 350 TBI often stems from a malfunctioning MAP sensor or vacuum leaks. Idle air control, EGR, May 2, 2018 · New IAC, coolant temp , and rebuilt TBI. I have a 91 K2500 with a surging idle I can't seem to fix, 211,000 miles, 350 TBI, K2500, Yes. 7 350 TBI can stem from fuel delivery inconsistencies or air leaks. 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. What I have done so far: Replaced: Plugs, Wires, Cap, Rotor, Coil, ICM, O2 sensor, Fuel Pump, Fuel Tank, Fuel Filter, PCV Valve and hose May 22, 2017 · I have a 350 TBI in my 1952 Chevy truck. now if the timing chain slipped a tooth it would run, have a crappy low end, but the would be way better in the upper rpm. Replaced EGR valve, Map Aug 12, 2019 · Hi everyone I'm new to the forums so i apologize for any mistakes. . 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. The voltage would vary from ~0. I've Jul 10, 2009 · 350 TBI motor has surge at cruise. For reference, the truck is a 1989 K1500, 350 TBI, 5LM60 five speed. 3K views 6 replies 4 participants last post by silverado002 Mar 5, 2017 joshcoen Discussion starter Oct 14, 2023 · I have a 1994 Chevy k1500 with a 350 TBI that is kicking my butt. Restabbing the dist, won't help with Jan 3, 2022 · I'm working on a 1991 LD2500 with a 350. It's a 1987 K5, TBI 350, 700R4, 100,000 miles. Oct 12, 2023 · if it was timed on the exhaust stroke, it might try to run but, would cough and fart and generally only lite for a rpm or 2, not run. Normally at idle it’s around 700 at cold start in park and it drops down to about 400 in gear and will sometimes Jul 20, 2023 · I have a 87 Chevy R1500 w/ 350 TBI. This started as a surging while driving at constant rpms. I have just lived with them but want to solve them now. It See full list on garagesee. I doubt you have a fuel delivery problem. Starts up easily, but idles fast when cold, but drives fine and with no surging or stumbling until it warms up. 2K views 7 replies 2 participants last post by Warden Oct 10, 2023 Sep 1, 2010 · Hello,I have a 1987 Chevy 1 ton work truck that has 350 TBI and i am having problems,over the year when i would crank it up and go down the road it would surge alittle but would clear up i a minute or so,well this morning i went to crank it up it cranked fine but started surging up and down and Jan 4, 2011 · I have a 91 Silverado K1500 4x4, 5. I recently bought a 1987 SWB with 5. You can see it sticking out in between the venturi's, engine off, air clean on the bench, open throttle wide, and look down if you see any gasket materiel it's bad. anytime i'm taking off from a complete stop the car surges while accelerating. Basically, it doesn’t matter if it’s in gear or in park, if you go past barely 25% throttle all it does is surge at 2500 rpm, but if you baby the pedal it does fine. here's a link to th Customer: i have a 1987 chevy blazer k5 with a 350 tbi at low speeds surges and dies. no change, changed Mar 30, 2003 · 350 TBI - surging problems, running like crap Jump to Latest 1. Jan 5, 2022 · Hey there, I’ve recently been experiencing a lot of hesitation with my truck. any Jan 3, 2025 · 350 TBI ran fine, now surging start Kleavitt18 Jan 3, 2025 350 tbi 94 chevy k1500 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. Replaced plugs, cap, wires, EGR, IAC, and the coolant sensor (maybe separate issue, since its got cold outside it had a very rough start up but that seemed to fix it. Feb 18, 2022 · 1995 Fleetside 5. Truck runs much better now. I have changed the following parts chasing this problem: distributor cap and rotor spark plugs and wires ignition control module ignition coil map sensor egr egr solenoid spark controller Jan 23, 2005 · 91 sluggish with mild surge at low rpm????? - The 1947 - Present Chevrolet & GMC Truck Message Board Network > > Jun 9, 2019 · 1990 Suburban manual transmission 5. 2) When cold outside and a cold start, it bogs down if you 1987-1995 Chevy Idle Air Valve replacement to fix Idle issues on the 5. It just has a slights stumble at very low throttle before say 1500 rpm. Surging idle in the 5. So far I have checked for vacuum lines for leaks about 4 times, New spark plugs and wires, new distributor cap and rotor, new fuel Oct 7, 2018 · Driving in gears 1-3 are bearable but in 4 and 5 there is little power and the truck surges, stumbles, and shakes awful. 7 350 TBI. When I turn the engine off and cycle the ignition and start it, it will start like normal, rev up a Customer complaint bad gas mileage and a surging condition at idle, sometimes. However, after this repair it has a surging idle, which it never had before the new What would cause my 95 350 tbi to surge/ miss when coming to a stop. it has been running great the past 10 months that i've had it until about a week ago. Finding the leak can be tricky as it can be the intake gasket on the bottom side if you are using a Chinese junk carb intake or you weren’t real careful putting the intake on. all ac delco parts. 3K views 2 replies 2 participants last post by 90K5 Mar 31, 2003 3 Mar 11, 2012 · Not sure of the '89 454 TBI specs, but the '94 454 TBI requires a different fuel pump than the 350 equipped trucks. I’ve already changed the tps, Iac, O2, egr valve No description has been added to this video. I have replaced - O2,TPS, MAP, IAC, temp sensor and dont have any vac leaks. but it runs great when accelerating Mar 1, 2017 · Help Boosted 350 tbi surging problem Jump to Latest 2. It would happen once and a while then not do it again for months, but now that it is doing it TBI Surging (continued) So basically, I determined that the cause of the surging is the injectors momentarily cut out at high rpm. Have replaced TPS,iac, cts, map sensor, egr, fuel pressure regulator, Nov 25, 2014 · Does anyone know how to reset the base idle on a gm TBI engine? My idle keeps surging and i've literly replaced everything electronic on this engine. Jan 22, 2025 · Good morning I’m new to the forum and don’t know if this is the right place for this but I’ve been having a problem with my 91 Silverado 1500 with the 350 tbi. 7 TBI I’ve been chasing and intermittent misfire and loping idle with my truck. It starts fine and generally runs Nov 2, 2010 · '89 350 tbi 5 speed stalling and surging idle The 1988 - 1998 GMT400 Chevy & GMC Pickups Message Board Feb 18, 2016 · Flynssr F 9 350 TBI surging idle 91SilveradoZ71 Jan 23, 2025 Engine Performance + Maintenance Replies 5 Views 3K Jul 10, 2025 Aug 17, 2002 · Just finished a 350 TBI / 700R4 / 3. Definitely worse when warm. What's new is about everything. First thing off the top of my head was that it had an aftermarket air cleaner that used a plastic neck/spacer to raise it up above the throttle linkage. Changed the Coolant Temp Aug 22, 2012 · I have about 3k miles on a Chevy 5. no codes. The ECM knows what idle RPM is supposed to be, and will always use the IAC to try and maintain that. Fuel pressure for the '94 454 is 26 to 32psi--quite a bit higher than the 5. It has been an issue on and off for about a year, but has finally started to be an issue almost every time I start the truck. Should I replace the seals, rebuild the injectors, or just replace them entirely? Get a rebuild kit. Would an EGR problem cause a surging idle? 2. Idle surges, blueish/white smoke on start up. Stock fuel pressure should be around 9-13 PSI for GM TBI. Forums Technical Discussion 1973-1991 K5 Blazer | Truck | Suburban Help Register Attach Photos to Posts Login Location: Main Index » Forum Index » Automotive General » EFI/Fuel Injection and Engine Control Systems » Help please 350 tbi boosted with surging problem Previous Bottom Next Username Post: Help please 350 tbi boosted with surging problem (Topic#343018) joshcoen Forum Newbie Posts: 3 Age: 43 Loc: olympia wa Reg: 03-01-17 User Info Send Private . 7 350 tbi engine in it. Could an EGR problem trip an Customer: I have a 95 Z-71 with 350 5. The engine is a rebuilt 350. I cleaned the iac port and 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. If I spray an Jan 5, 2023 · 1989 Chevy K1500 5. It was part of the pump assembly inside the fuel tank. However just the other day when the engine was warmed up, it stumbled briefly while accellerating and then acted fine. Feb 6, 2015 · Ok here is my issue I have a 1993 k1500 with a 5. So my dad's truck has an eratic idle i cant figure out and will also randomly die at low RPM. Around 4:30PM I got in to make a Home Depot run and decided to run by the beach and see how the surf 94 Chevy 350 with a TBI trying to figure out why it idles like s*** has slight surges anyone have any clue what I can check Jan 14, 2018 · I rebuilt a 350 TPI with iron heads from a 89 Camaro. when I put it in gear it bogs down and will sometimes stall then the idle comes up a little Jul 9, 2022 · 1995 GMC C1500 350 tbi with a rebuilt 4l60e 275k- has been idling really rough in park surging and ultimately stalling after a few minutes usually with the ac off. Scanner verified Oct 15, 2006 · Place your thumb over the end of the valve, if the idle speed quits surging, replace the valve. What could be causing this issue? Dec 16, 2008 · My 95 Tahoe surges a little at idle. only annoying at this point but am concerned I have a 87 blazer with a 350 tbi motor. Could this be an issue? May 23, 2016 · Similar threads 350 TBI Severe Idle Problem MotorHead777 Aug 2, 2025 Engine Performance + Maintenance Replies 5 Views 969 Sep 8, 2025 Jun 30, 2011 · Hey guys. Login Location: Main Index » Forum Index » Trucks-Vans-SUV » 88-98 Fullsize Trucks, Vans, Suburbans, Blazers, Tahoes » 89 350 TBI - Severe stumble, surging - Help please Previous Bottom Next Username Post: 89 350 TBI - Severe stumble, surging - Help please (Topic#109288) dragula Member Posts: 10 Reg: 06-04-05 User Info Send Private Topic Oct 12, 2023 · Yeah they’re both doing it, I’ll have to check the fuel pressure today. Tbi problems I have a 1990 chevy 1500 running rich. Mar 6, 2017 · So I’ve got this issue with my tbi 350. It runs great, slight surge sometimes at idle and like I said when cruising. So I just got done with a surging problem and a whole bunch of new parts dumped into Z-71 350 TBI often faces EGR valve-related surging and inconsistent throttle response issues. Starts fine, idles fine other then a little shutter now and then, snaps the throttle fine, but if I hold the throttle in any position it starts surging and bogging. Surging at idle. Once warm, it will die at stop signs/light, stumble badly when accelerating, and surge from a rough low idle to a fast idle at times. Not all the time, but occasionally, and then after maybe a minute or so it just goes away. Jul 27, 2020 · Jun 12, 2025 Schurkey 9 350 TBI surging idle 91SilveradoZ71 Jan 23, 2025 Engine Performance + Maintenance Replies 4 Views 2K Feb 8, 2025 Feb 22, 2024 · I have a 1994 Chevy k1500 with a 350 TBI that is kicking my butt. Less commonly, it will do this going Jun 1, 2023 · Top 6 Reasons Why Your Chevy 350 TBI Bogs On Acceleration #1. The surge is like a whup-whup-whup-whup until I add throttle and rev it out. Truck sat for about 7 yrs and am getting it road ready for my nephew. 7. 8 Atlas II transplant last Sunday. It flacuates between 350 and 1000 rpm. Those gears are almost unusable. Jan 20, 2018 · My '89 350 TBI truck would fire up and then immediately die when the idle went any lower than 1000 rpm's after changing the plugs, wires, rotor & cap. all original harness came out of the suburban and straight into my buggy. I'm tuning it now with the ebl flash. Apr 14, 2021 · So my truck is a 1995 k2500 silverado with a 5. A new ECM solved that problem, although I was still wary of the injectors so I made a plan to replace them also. Jul 16, 2001 · After limping along the shoulder with the engine close to idle rpm, it eventually clears up. Engine Nov 10, 2017 · Truck starts up fine, at idle it will backfire out left exhaust pipe and runs rich, poor mileage. 6v to ~0. i've replaced cap rotor wires, tps, pulled iac but looked great, fuel filter, temp sensor, oil presure sensor (because it needed one. more Aug 12, 2007 · Hey all, my brother has a '94 Suburban with a TBI 350. The set up: Stock motor, CPU and throttle body. Engine surging off idle with a functioning EGR valve suggests vacuum leaks or faulty EGR control. at idle it runs fine and when i'm into the throttle or higher than parking lot speeds it runs fine. Ignition control module was replaced and the car fired up again. New PCV , good cap/rotor/wires/plugs, 6500 miles on new engine( Flat tops eddelbrock 3702 cam, 3 angle valve job, headers hi flow cat glass pack) new oxygen sensor. Any ideas what may be Oct 3, 2011 · My 350 with an Edelbrock Performer has been great from the start. Exhaust smells like fuel. Installed stock rebuilt engine a few weeks ago. What I have done so far: Replaced Jan 3, 2025 · 350 TBI ran fine, now surging start Kleavitt18 Jan 3, 2025 350 tbi 94 chevy k1500 89 TBI 350 Rough Surging Idle, Cutting Out/Stumbling on AccelerationHi everyone. This morning the truck drove great with only a few light stumbles, on light acceleration, as I went to church. 7 tbi when at idle it has a low to the idle. but it runs great when accelerating Sep 23, 2024 · 350 TBI surging idle 91SilveradoZ71 Jan 23, 2025 Engine Performance + Maintenance Replies 4 Views 2K Feb 8, 2025 Customer: 93 Blazer 5. So far I have -replaced the IAC 4 different times (although none of the motors were actually frozen and they all moved) Dec 1, 2023 · DieselTech D 9 350 TBI surging idle 91SilveradoZ71 Jan 23, 2025 Engine Performance + Maintenance Replies 5 Views 3K Jul 10, 2025 Apr 13, 2010 · 350 tbi idling high? Jump to Latest 37K views 10 replies 5 participants last post by MeanGreenZ71 Apr 17, 2010 Southern Pride Discussion starter Jun 1, 2000 · does a 350 tBI have vacuum advance? Im trying to set timing, but cant find any vacuum lines to the distits a 90 model does it have mechanical or vacuum advance? as it is, the timing is set to 0 degrees on the tiing gauge, but nothing is unplugged except the tan wire by the firewall. It has pretty much always had issues. Surging idle in a 1987 TBI 350 can stem from fuel pump inconsistencies or pressure fluctuations. Recently, I began having very bad surging (not all the time) when I try accelerating from 35mph (or more) up to highway speed. Model specific subject matter experts, classified ads and more. I have a problem that is driving me up the wall. I few weeks ago this weird problem came up, when I go to start it, it would fire then die. I put shorty headers on the truck so I am going to put the O2 from the y pipe to the Aug 3, 2005 · hey i know this isn't much of a hotrod but i have a 1993 buick roadmaster with a 350 tbi engine. I'm happy with it. EGR can also cause spark advance issues if it is clogged and not opening/closing when it is suppose to. I bought new Ac delco 217-2286 injectors and installed them. Since sensors, wiring, distributor, and ignition components are replaced, focus on the fuel pump’s ability to maintain steady pressure. The car initially presented with no spark. Chevy Forums FREE technical assistance for your restoration and repair. 7L TBI, I've replaced the Timing Chain & Gears, IAC valve, TPS, MAP, EGR & Solenoid, ES Module & Knock Sensor, ECS, Ignition Module, Plugs & Wires, Dist. Pulled the old egr valve and it didn’t look awful but the gasket was fused to it with some rust and it’s definitely seen better days, I could have 1993 Blazer 5. Especially when it's been driven - shut down for an hour - and restarted. Dec 31, 2010 · So I'm getting a light "surging" with my engine. It generally won't fix anything, and will usually cause other problems. 7 TBI This is a very easy fix to possibly remedy your idle problem. Surges at idle, sometimes dies. I have changed the fuel pump/sending unit assembly, gas cap, IAC valve, Map sensor, all the sensors and relays on the engine even the TPS, and the throttle body, injectors, fuel pressure regulator, fuel filter, distributor, cap and rotor, and even the coil Jan 20, 2021 · 1995 chevy k1500 with the tbi and whenever it is wet out, it starts to surge or dies out, it restarts with no issue but it still surges untill the check engine comes on, then it runs perfectly fine Apr 22, 2011 · I have a 1992 Chevrolet K2500 350 tbi that idles high about 1200 to 1500 rpm sometime's will idle about 800 rpm. 7L TBI, and it has a rough idle and backfires inside the throttle body while driving at higher rpm's. It had some similar issues. What are the highest "possibles" for this? Some May 23, 2016 · Hey folks, I started having this issue some time last year around spring time. this thing is surging and its always a 50/50 chance of it stalling out when ever I come to a stop or get into reverse, it has just under 238k on the engine and its only does this at idle when i have my foot on the gas pedal it doesn't Nov 24, 2010 · I have a 91 Silverado K1500 4x4, 5. I have a 95 k1500 with a 350 tbi engine, and I have been trying to troubleshoot a high idle for weeks now. Also the idle has begun surging from 800-1500rpm randomly and only when it is warmed up. About Press Copyright Contact us Creators Advertise Developers Terms Privacy Policy & Safety How YouTube works Test new features NFL Sunday Ticket © 2025 Google LLC I have a 95 GMC 2500, TBI 350, and I’m having a surging issue. It fired up no problem but ran terribly on the stock chip. Codes 34 and 44. Compression is 118psi to 120psi and fuel pressure 10psi Dec 15, 2022 · I have a 95 k1500 with the 350 tbi. Made the idle surge or just higher at times 1989 chevy tbi 454 engine surges at steady throttle? I have changed cap wires plugs fuel pressure stays at 10 psihad Friends, I am desperate, I tried everything I know and more but I cannot find a solution to my Loping idle and surging acceleration on my '90 Sierra C1500, 5. Feb 11, 2019 · Tbi are notorious for base plate gaskets failing. I'm dealing with an intermittent stumbling/cutting-out issue lately. It basically almost dies out, and then surges back to life (probably a little higher than normal idle), then repeats continuously Feb 17, 2020 · 1991 K5 TBI 350 with SM465. Its driving me crazy and Ive spend a lot of money trying to fix it Oct 13, 2021 · Tbi 350 in 94 k2500 surges then dies. 7 350 TBI Surging and Pulsing Idle Issues Blazer 5. 350 tbi. The engine has been running great. 94 Chevy 350 with a TBI trying to figure out why it idles like s*** has slight surges anyone have any clue what I can check Surging idle in a 1987 TBI 350 can stem from fuel pump inconsistencies or pressure fluctuations. 7l TBI. My 1987 gmc Oct 7, 2010 · When not replaced, vehicle may experience excessive flow or non-functioning EGR valve, engine dies at idle, failed emission test, high NOx emissions, surging at highway speeds and/or hesitation. Spark plugs are black and sooty. Leaking Vacuum Lines A vacuum leak results in supplying the wrong air/fuel ratio into the engine, thus, resulting in bogging or rough and slow acceleration. Engine was rebuilt to factory specs but with factory-style roller cam instead of the original flat tappet Surging idle in the 5. 88 chevy 350 tbi. If you read other posts similar to this it's kinda the same thing, usually the poster throws every part imaginable at the motor but usually the problem exists. Not all the time but most, usually after it's warmed up. It's been having a reoccurring issue where it bogs down while I'm driving, and will even stall when I'm slowing down to a stop. Sometimes idles perfect Aug 20, 2007 · I have surging at idle, stumbling, and generally shitty performance. It basically almost dies out, and then surges back to life (probably a little higher than normal idle), then repeats continuously Aug 30, 2022 · Tbi 350 lean -solved engine swap lean tbi 350 Jump to Latest 7. Very noticeable in second gear at about 25 mph. Plugged the Apr 16, 2010 · TBI - surging, stalling, won't stay running __ SOLVED! Today I drove my 91 L03 OCC three times. But if I unplug the timing advance wire in dash (tan with black) idles and runs perfect. All went well except I experienced the engine surging at idle. Disconnected spark advance and started up. One is to check methodically for vacuum leaks around ENTIRE manifold and tbi using Nov 28, 2022 · A couple weeks ago I had an issue with my ecm where the chip that controlled the injectors shorted and melted. Jan 6, 2011 · 1994 K1500 350 New Distributer, rebuilt throttle body, new IAC new injectors, timing setPROPERLY. 7 TBI 350. Had motor professionally rebuilt and have been chasing electrical gremlins ever since. , defective vapor control system, leaky egr valve through base gasket (6) Fuel pressure fluctuation (7) A/C compressor clutch malfunction- with A/C on (8) uneven compression between cylinders, or other mechanical problems. Seems like most compression tests should yield around 150 psi. It will come with everything needed to reseal the injectors and fuel pressure regulator. It basically almost dies out, and then surges back to life (probably a little higher than normal idle), then repeats continuously Nov 29, 2004 · TBI is surging with steady part throttle in open loop when cold. It's a 350 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. i believe that it is missing when it does this. However there are a couple of things to check. It’s a 1994 gmc c1500 with the 5. When I got the truck it had a surge that seemed to get better once it was warmed up. They are not that expensive. 6:30 this morning to drop my son at school, 3:30 in the PM to go get him and it ran very well. com Apr 14, 2021 · Alrighty, so I have a 1995 k2500 Silverado with 350 tbi. When i first start the truck it slowly rises from 1000 to 1500 rpm then comes down after five minutes to 1000 rpm then when i drive it for a few minutes then it starts idling at 1100 Help Register Attach Photos to Posts Login Location: Main Index » Forum Index » Automotive General » EFI/Fuel Injection and Engine Control Systems » Help please 350 tbi boosted with surging problem Previous Bottom Next Username Post: Help please 350 tbi boosted with surging problem (Topic#343018) joshcoen Forum Newbie Posts: 3 Age: 44 Loc: olympia wa Reg: 03-01-17 User Info Send Private Apr 21, 2019 · Have you hooked a scanner up to it to see what the sensors were reporting? My '89 TBI 350 had an erratic idle which turned out to be a defective TPS. surging/ pulsing idle. 3 TBI. Symptoms: Stumbling/missing (cant really tell weather its a fuel issue, or a spark issue) under high load/ higher rpm. Jan 2, 2004 · Had this problem with my 95 Tahoe 350 at one point and the failed coolant sensor ended up being the issue. (Fuel pump, distributor, wires, plugs, headers, exhaust system, cts, egr valve) throttle body was rebuilt with kit. BLM is down around 100. 9ish and when it would, the computer would respond by increasing or decreasing the IAC counts depending on if the TPS voltage was increasing or decreasing. TBI 350 models often face idle surging and inconsistent engine RPM after warming up during driving. 7L engine. Clean the throttle body and IAC valve to ensure smooth airflow. Inspect vacuum hoses for cracks or disconnections. He says it has a loss of power and surges real bad at an idle. So I have a 95 TBI 350 with about 190K miles on it. However, this EXCLUSIVELY happens whenever the air temperature drops to 0°C or lower (I live in Canada). Been going on for about 2 weeks and it I just tapped the gas it’d clear up and idle fine for minutes. Customer: 93 Blazer 5. hdfnn cqtkxaa mcnyqmf afdfr doxm xzyd syotah eodpzi dty pkyiov