Tbi wont idle down. I've replaced the TBI / manifold gasket .

Tbi wont idle down Is their anyway to lower the idle on a throttle body. 84' cj7 ,Howell TBI wont idle R. The chevy runs great, lots of power and smooth. 191 seconds. Redcolt88 Jeeper. It will bog itself down and eventually cut out loping high idle, extremely low idle (low enough for oil pressure light to kick on occasionally. I disconnected the CTS and it changes the idle. 5L TBI wont drop rpms after warming up. 8L TBI, 5 Speed Borg-Warner T5, cats & Y-pipe cut 4 dual-in/dual-out muffler + pair of 30" glass packs, Stewart Warner Gauge Ultra Shift tach (blue shift light), contoured bug deflector, external sun visor, fog lights, 15" full size light truck tires, and Alpine head unit, 200K+ miles as of June 2010. sensor is reading correctly,if reading higher temps then should be it will cause the computer to read that it needs less fuel,causing a lean condition. adjust the T15 screw in the front of the throttle body to get there. when you drive down the road it acts just fine plenty of power and when i come to a stop it dies out again and is really hard to start back. After further review I decided to do some preventive maintenance while the engine was out of the boat. TBI, Engine Shuts off after slow down to idle. A 350 TBI idles up and down at random is one of the most common. Just makes them run dark. I just get a very quick OL when I get around 4. The RPM's would go up and down and then go back to being smooth and come back later. Jump to Latest where is it idling at? 900+/-50 is the correct idle. Before this issue, it has always idled at 1500 rpm on startup and takes awhile to idle down. I have to run it with a little throttle to keep it going and it smells like it is running very rich. Will start back up fine without the cold start but will only idle for 1 to 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. 80. The RPM on my engine does not come down when I come to an idle. I left the air filter on and sprayed the cleaner at the base of the tbi system all the way around. If so the valve is sticking open. On a cold start first thing in the morning it will crank fine but will not fire. I have used it for testing just about everything on my jeep. 4 won't idle The 1988 - 1998 GMT400 Chevy & GMC Pickups Message Board. Truck sat for about 7 yrs and am getting it road ready for my nephew. 40 - 3. should idle down and be normal for a second or 2. If you have 10, Usually o2 sensor issues won’t foul plugs. 1999 ZR2 Blazer 4. 1. 166 seconds. Location: Main Index » Forum Index » Trucks-Vans-SUV » 88-98 Fullsize Trucks, Vans, Suburbans, Blazers, Tahoes » 93 5. And being that the engine had 300k miles on it I had it It will sometimes sit there and idle normal and dip down sounding like it will die, and sit there and do that. With no throttle, it won't start period. 1 Welcome, Guest. Checked fuel pressure. Also the bike runs rich I attached the lowest drop and highest drop. as for rich or lean I have pulled number 1 plug and looked at it and it's the normal running colors tanish brown I have not pulled any others out 1994 1500 5. i have to keep my foot on it for about 5 min. 89chevy4scrap; Apr 16, 2024; Engine Performance + Maintenance; I've got a 92 Blazer 4x4 4. Mine has been disconnected since I got the truck. until it smooths out. It seemed to be struggling with idle so I turned the connector for my IAC 180 degrees and tried again. Register or Log In To remove these advertisements. TOday it won't stay running by itself at all. User Info. 9. 89 TBI 350 Rough Surging Idle, Cutting Out/Stumbling on Acceleration which seems to coincide with the idle bogging down. TBI 454 idle problem. Someday I’ll do it just to clean it up. 7 TBI This is a very easy fix to possibly remedy your idle problem. 1989 P. One out of five times the idle will seem to fall out when taking it out of gear and coming to a stop. Locate the idle air control My truck in question is a 1988 GMC Suburban V2500 350 TBI / TH400. - New fuel pump and fuel filter. Anything below that and it's fine and above it hangs open. 89 D150 318 TBI auto Symptoms: When I start it up it idles normal. zip (0, 1 view) Got a down draft system won’t idle below 950. I did use these instructions to reset the idle on the truck and the IAC Position is open about 6% at warm idle 87 Chevy 350 TBI low Idle issue The 1973 - 1987 Chevrolet & GMC Squarebody Pickups Message Board Register or Log In To remove these When the engine is started, does the engine have a fast idle that slows down as it runs? The IAC (idle air control) Removing the hardened, tamper-resistant cap from the TBI base and adjusting base idle to 500 RPM in drive (with the IAC air channel in the TBI base temporarily plugged and ignition timing set to zero with ESC bypassed) will benefit idle quality and off-idle driveability issues and also help with the standing wave in the belt (that I suspect is audible inside the cab Reconnected the line. Before I had the engine rebuilt it was doing the same thing, I checked the cam lift and it was way under spec. It's definitely getting worse. Jump to Latest 41 - 54 of 54 Posts. Idle goes up and down about 100RPM, it happen suddenly and quite often. After 2 years and having the burb at 2 different shops with no result to the surging idle, I stumbled upon the answer at a Ford site. 10. Unplug the IAC valve located on the passenger side, rear of the throttle body. 0 Click for thumbs up. 2011 Wed, I bought some dry gas and mixed it with 3 gal of fresh fuel and dumped it in. 350tbi won’t idle. if Normal idle is a bit higher. The IAC 350 tbi idle I bought my jeep with the 350 already in it, ok with that said my IAC is bad i tested it and when i cover the hole my idle come back to where it needs to be. I have one continuing problem that I have been unable to solve. 1985 W250, 318, 435, 208, 44/60 1991 W350, 360, 435, 205, 60/70 8. THEN see what you controlled timing is. Looking at your read out I'd be looking at that open loop and low coolant temp. Apr 23, 2022 • 1989 Chevrolet K3500. 6. It'll start but only if the pedal is all the way to the floor and won't stay running on it's own. From what I am seeing on other forums (in the truck/corvette/etc) 454 TBI Suddenly Will Not Idle, Dies at idle - SOLVED. Looks like I'd have to loosen a clamp somewhere down the fuel line to get it to flex far enough back from the 454 TBI Suddenly Will Not Idle, Dies at idle - SOLVED. Idles great and runs great when warmed up. 7L tbi and timed it. 1044300 my 90 yj 2. Email Report Chevytech Subject Blazers, Tahoes » 1995 C1500 V6 4. I think turning it counter clockwise closes the throttle blades and clockwise opens them up more. At slow speeds and under load the oil pressure drops to 5ish and stalls out. 65sohc @65sohc. I read where you need to reset it via the underdash port so it can "find home" or something. It will sometimes sit there and idle normal and dip down sounding like it will die, and sit there and do that. also had problems with the mechanism connect the butterfly’s in the bodies coming loose. My truck is an 87 R10 with the 305 TBI. I've changed The backfiring has diminished with the timing corrected, but it won't idle. I adjusted timing and it didn't fix that. 1 answer. What's new Search. Thread but it usually won't stall. Stopped and the whole truck was shaking, reaked like fuel. 1 ©2003-2006 InteractivePHP, Inc. Mine was doing the same thing and I narrowed it down to a vac leak because after I rebuilt the throttle body with fresh gaskets it went away. I disconnected the Idle control solenoid, started the truck, ran the engine at around 1200 rpm for about 2 minutes, and it actually idled at a low rpm with no input from me until the engine warmed up to operating temp then it Check vacuum lines, IAC and be sure you have good clean grounds. Now TBI Slant 6: Joined: Fri Nov 30, 2007 7:08 pm Posts: 130 Location: Kerrville, TX Car Model: Playing with the motor more today and still I only say that because I have done it myself and spent several hours chasing down why the ( see image ) When I disconnect that vacuum line the idle drops down but it runs badly. Finally nailed it down to a vacumn leak at the intake manifold (loose tbi wont idle « on: July 23, 2011, 05:42:45 PM » I have just done a tbi conversion to my 84 Scottsdale with an sm465. It's throwing a code 22-TPS signal voltage low/fuel cutoff relay circuit, open or shorted to ground and In this video, I will show you how to set the base idle for your Chevy or GM V8 engine. I restarted the engine and drove it, but it would stall when I would come to a stop. Hooked up the scanner today and see that at warm idle, my IAC was dropping to 7-13 whereas I recall it generally stays around 30-40 at warm idle (been a little while since I've scanned this truck). When the choke is turned off, it won't idle. Runs like complete crap at idle, and clears up as you get up into the RPM Okay I will try to get all the info in one shot. Slow to get down to idle could possibly be a failing or dirty IAC (idle air control) motor. 350 tbi idling high? Jump to Latest Hey guys, lately my truck will randomly kick up the idle in park to around 1200 rpms. I thought I was on my way but when I put it in gear it begins to sputter and backfire. My air bypass screw is set to 2 turns out. with throttle or without. I disconnected the Idle control solenoid, started the truck, ran the engine at around 1200 rpm for about 2 minutes, and it actually idled at a low rpm with no input from me until the engine warmed up to operating temp then it would no longer idle without surging or throttle input. Pretty much any of the cams I recommend or have listed on the website will pull at least 17-18″ of vacuum at idle. What's new. I am working on a 1987 Chevy 1-ton that has the 454 with TBI. I can start it and it will run anywhere from 10 seconds to 2mins, it studers then will idle up and down before it just stops. like 1200 RPM's and wont go down. Looking down into the TBI with the engine running, the IAC motor appears to be operating correctly. sounds lumpy. I replaced the fuel filter and fuel pump and my dad put a gauge on the supply line and said it was in spec. I tried adjusting the idle screw but mine is capped from the factory. My issue all started when I went to get it smogged last year. The best way to determine if your idle air control valve is the issue is to check I am working on a 1987 Chevy 1-ton that has the 454 with TBI. Voila it ran beautifully! Today I replaced my O2 sensor and both CV axles. Runs great without it plugged though which leads me to think Chevy 350 won’t idle. IAC, EGR, EGR controller, MAP, temp sensor, vacuum leaks, O2 etc. If you’re noticing that your RPM are constantly going up and down, even when you’re not accelerating, it’s likely that you have a bad idle air control valve. The bike runs really well down low now except for a hanging idle that seems to get worse as the bike gets hotter. It seemed like It won't idle. It will start back with a little throttle but refuses to idle. Finally installed set screws. Hard start and won't idle. It idled fine, but the next day it started doing the same thing. no luck, and i smelled gas, so I held it to the floor, and it fired right up, but blew black smoke, smelling like gas(of course, I think I unintentionally flooded it). The power booster for the brakes you mentioned, seems to be fine. I went ahead into town, shut the engine off and back on a couple of times and now it appears to be idling correctly. With the cold start it will idle strong but as soon as I release it the idle slows down till it dies. It won't idle on its own, you have to step on the gas to keep it going. most of the time it idled just over 1000 rpm. Short story it failed 3 times for high NOX @ 35mph. 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. What (fluctuating up and down). 7 GSi with TBI worked on by a shop here in San Diego (I I have an 89 TBI 4. then turn off the truck and plug in the IAC and restart and see if idle is correct. Still like that trying to call tech or they tell me to call streetmaster. G The narrative says oil/fuel switch shuts the pump down if the oil pressure drops, say due to an accident. adjust the screw until idle is in the 450-475 RPM range. The engine runs fine while riding performs perfectly the problem never gets any worse or better. I never heard the rpms change at all. I’ve replaced the iac valve and done the relearn procedure and still nothing. I've replaced the fuel filter. I stumbled across this post: I use pliers to pinch off vacuum hoses and listen to see if it slows down. It got worse over time and now it when that happens the RPM's go up to about 1200 max and down to almost dead a few times and eventually it can't recover and just dies. 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 turn it off when this occurs. all original harness came out of the suburban and straight into my buggy. i have a 1989 350 tbi i was driving it the other day and it wasted acting up had no power and ran Ruff got it home to look at it. Same '89 Blazer with the 2. It runs good at highways speeds otherwise. This will apply mostly to 1987-1998 vehicles with Throttle Body Inje In this video, Hooked up the scanner today and see that at warm idle, my IAC was dropping to 7-13 whereas I recall it generally stays around 30-40 at warm idle (been a little while since I've scanned this truck). I am thinking of 'scoping the idle speed motor wires, but I don't know what to expect. If I prime it by spraying ether or fuel down the intake than the injectors will start spraying and the vehicle will run, as long I keep the throttle down. It does idle low in reverse though. Read full answer. warm up engine. It starts fine and goes right to a strong idle with the choke on. when I put it in gear it bogs down and will sometimes stall then the idle comes up a little bit and continues to run rough. Put in gear it will die. Long story short , on a drive, coming up to a stop sign all of a sudden I noticed my idle drop way down. I am amazed how nice it idles now. 3L is having issues idling and poor throttle response from idle. If I leave it disconnected it wont restart. You need to warm the engine up and cruse at about 40 - 45mph steady for a bit. 5L TBI engine. I have to jam the gas pedal all the way to the floor to get it to go, but that only lasts a few Also check the TBI base gasket for leaks. My thinking is when the motor is cold the pintle is retracted all the way. Redo IAC relearn. I guess the other question would be if I had to adjust the idle on my stock tbi. I have driven car about 200 miles. Let me know if the new gaskets fix your issue once you button it back up. adjust idle screw behind it to about 500 rpm with IAC closed. I just put new heads on my 5. From what I am seeing on other forums (in the truck/corvette/etc) I swapped my TBI out for a remanufactured unit. The SES doesn't come on for It is surging heavily at base idle. It ranges from 1300 rpm to 1700 rpm and bounces back and forth. When I Seems I have a Howell TBI and just had my v-6 Dauntless rebuilt and installed a Snider Cam and have the same hunting problem at idle. Recently did a It still idles low and kind of unsteady out of gear but not in gear at idle. The next day it wouldn't even start unless you used starting fluild or poured gas down the throttle body. The most noticeable symptom of low fuel pressure on TBI trucks is poor idle quality. 1992 Chevrolet K1500; Chevrolet so when u turn key on fuel pressure should go up within 1-2 seconds on gauge. cotton shop rag stuffed into the idle air bypass port which is behind the passenger side TBI hold down bolt. If it helps, think about it as a 1987-1995 Chevy Idle Air Valve replacement to fix Idle issues on the 5. It runs fine but it idles at 1100 rpm in park once warmed up and about 900 in drive. Engine stalls when you come to a stop, after the engine warms up. 1991 K5 TBI 350 with SM465. It will die without some extra throttle. 1 2 3. If I give it a little gas it wants to stall and then the idle surges up and down then will even out or stall. I think you need something like 5 seconds. I have a 87 Chevy R1500 w/ 350 TBI. I can ride 100 miles and it still won't idle or start without giving it a little gas. Once I got it hot then it idled real fast. Sprayed the vacuum lines, TBI to manifold flange and all along the intake for vacuum leaks. Other than the idle, the truck runs fine. It is a 1987 Chev Silverado with the 5. and absolutely no power. Recently rebuilt/resealed the TBI, and put in a new distributor and set timing. 1987-1995 Chevy Idle Air Valve replacement to fix Idle issues on the 5. A bad idle control valve can also lead to fluctuations in the RPM. I played with the EGR while running, I can affect the idle while applying vacuum to the EGR. Too low may occasionally stall or surge. If I stop holding the gas it will chug down to 400 rpm until it stalls. iac is possible,try this first since its so common and let me 1992 caprice 305 tbi won't idle I have tested resistances on iac, replaced the air temp sensor, replaced coolant temp sensor, tested a spare map sensor I had and no change. I have pinned out the PCM grounds and checked circuit resistances (all good), All scan tool parameters are within proper operating ranges. Step 1. Incorrect idle speed: An IAC valve that sticks in the closed position will create an idle speed that’s too low. The truck eased forward and brought the idle down to 680-730 - it's always fluctuated a bit. 79 F-150 302,np435, rest of the truck has been sold and is now retired. if When I start it up cold, it idles high (which is normal) then idles down, but as soon as I put it in gear, and back to park, it sounds like a freight truck. I have a 1988 S10 Blazer 2. Replaced fuel filter. The e-prom needs to be programmed for lower vacuum, so Im told! The problem is that I have a rough idle when I start it up, but it doesn't stumble during acceleration. The problem is that the engine idles fast and I have to step on the brake firmly at stop signs to hold it from creeping forward. Re: extream high idle problem on 1990 chevy 1500, 4. If it fails it The next day it wouldn't even start unless you used starting fluild or poured gas down the throttle body. Their is a adjustment for the throttle stop but it has a plug in it. Disconnected spark advance and started up. The stock file is my GCF. Just won't idle Somewhere along the line the surging stopped while driving and started only happening at idle. Greg . Once that was in it seemed to run WORSE. It won't idle. Also, if I put it in park, the engine will idle down somewhat but when I put it in gear the engine will stutter for a few seconds and then idle up again. When I rev it up and let it return to idle it almost wants to stall out and idles around 650rpm. it will startup just fine but when it idles down it just dies out most of the time. after i had the engine installed and connected i made a very stupid mistake (I was very tired!), first connected the positive cable to the negative battery terminal, and when i brought the negative cable close to the positive batt terminal, there was a big spark. If vehicle is started with starting fluid it will stumble to life As the title states, I have the howell tbi system on my jeep. The GMC runs okay most of the time, cept for when accelerating. Found on the web that the cam brings the vacuum down so the unit enriches then the O2 sensor leans it out in an endless cycle. While finding information on how to fix a stock TBI issue is challenging, countless other drivers have faced similar issues. I have a 97 Suburban 5. I have replaced several items because of The idle was in range for a cold start and even idled down as it warmed up!!! However, it ran rough the whole time even after warm up and when taken out for a test. When i start one up after sitting overnight i always let it warm up for atleast a minute befor driving (usually longer). Here are a few potential answers: 1. Search Fixya. Then checking if the idle comes down when you block the port with your finger. I will never use this system again. Send Private Topic All of you keep mentioning vacuum leaks, so tomorrow I focus on that possibility. - Chevrolet 1987 Blazer question. i have a tbi 350 out of a 90 suburban in my jeep. Set the timing again, if it idles high remove the linkage. I set the timing (per Chilton's) and after I got it tuned up and running great it started with this stumble just off idle, mainly when coming back to idle. Hard to describe. Got to where I was going and back home again. Jeep will not start back up once shes been running or after she stalls unless she sits for 10-15 minutes, and she will start fine but a little rough. I use different Any feedback would be appreciated, sorry for the quality. 3 Need help troubleshooting TBI/IAC Idle issue S10 S15 Luv Blazer Register or Log Idles too fast, 2000 rpm when started cold, revs go up and down for awhile, then down to 1500 for awhile, then Plugged IAC back in, but engine still won't start/run. Finally nailed it down to a vacumn leak at the intake manifold (loose We tried lowering the idle rpm on the hand-held but it really didn’t do much and it should idle where we tell it to When any of the EFI companies build a product like a self-learning TBI system, 30003 system on 351w after engine gets to 170 temp won’t ideal. (NO JOY) I can hear the Fuel pump priming and it sounds fine. When I hit the throttle, there is hesitation, but then it picks up. A restart later yielded a surging engine that won't keep an idle. . 523 WOT and what appears to be a brief dead spot somewhere around 4v, but I can't pin down exactly where. Cold start idle to warm is fine and truck idles around 650/700 according to cheap tach. Before the motor was pulled it would stall when put into gear every once in a while, never threw codes, ran perfect other than the stalling. I whiped that out in less than an hour, was obivious as soo as I got the TBI loose that the thing has been sucking in air for a long time. I touch the gas and let off and it stumbles bad. Check the ECM coolant temp sensor as well, not the one in the head that reports to the gauge on the dash. Login Go Down. Same deal happens when I come to a stop sign. Chuck. I even adjust the decel open IAC down to -20 then -30 and it will idle down to around 400 rpm's nearly snuffing out but come back to around 800 rpm's. It only happens above 1800ish RPM. In closed loop my Integrator was also down to 118 when it was rough running, so I assumed I had a fuel issue. 7 TBI won't idle when it's warm (Topic#224368) 9C1DRVR Forum Newbie Posts: 13 Loc: Central Coast, CA Reg: 08-20-09. Also recheck timing with wire by brake booster unplugged. On hard acceleration it is bogging down like there is to JET TBI Spacer, JET Did you look at your temp sensor cause mine did the same thing it would idle real rough and the first start every morning was horrible and for the first 2 . I have had this truck for about 3 months and the idle is to high . Idle surge or idle hunting and high idle. To be honest my eyes aren't as good as they once were. this is BASE IDLE SPEED adjust so its lower than normal idle but won't stall. Unstable Discussion starter. I had my 2001 Striper with 5. Running a bbc with coil - Truck is a 94' Yukon, TBI. zip (0, 2 views) Sniperdriving. She runs if I give her gas, but will not Idle on cold. Another weird 350 tbi idling high? Jump to Latest Hey guys, lately my truck will randomly kick up the idle in park to around 1200 rpms. BTW, the vacuum advance can may be giving too much advance- you only need about 10-12 degrees from it, an adjustable can may be the ticket- but for now, run what you have. 210K miles feb. It seems if I could tweak the throttle stop a half a turn it would cure the problem,but the manual says it's not adjustable. I have a 1988 chevy 1500 with 305 tbi truck wont idle when i give it gas it bogs down look at tbi when its running Customer: i have a 1988 chevy 1500 with 305 tbi truck wont idle when i give it gas it bogs down look at tbi when its running doesnt have a fine mist coming out of injecters. 3L engine in my S10 From a fast idle, when I blip the throttle the car torques right, so the engine is making power. But if I “blip” the throttle it’ll jump to 1200 then like 1600 and hold there for a split second before slowly dropping down. Got some water in the intake last week. Runs great if you hold the throttle a touch or are accelerating. My 89 S10 4. It cranks right back up normally on the next try. It is very sluggish You need to check pressure at idle and WOT to ensure you're getting the right volume for your setup. It's very similar to what our 454 TBI did. Author Topic: 87 idle surging/stalling issues (Read 5473 times) tc197. If you set an SES light by having the IAC disconnected, then after shutting down the engine disconnect the negative battery terminal. It has made NO difference. Truck would want to idle @600-650 RPM when warmed up but often while just sitting there already idling at 600-650 it would start to idle up to almost 1,500 rpm at times. I have 2 gmc k2500 manual 350 tbi's, both have the same issue. Hey guys I have a 95 gmc k1500 wit a 350 tbi. 7 GSi with TBI worked on by a shop here in San Diego (I I have read nearly every thread on tbi surging idle, code 44's (lean o2), and everything in between. Also stumbles and occasionally will stall when first started in the morning. Hi All - I have a 21 300 XC-W TPI that all of a sudden won't hold an idle and is really boggy on the bottom end. 7 350 TBI. The truck does not like to idle with a thermostat in. I recently installed the idle screw mod and set the idle to the factory settings. Plugged the Re: 87 4x4 -TBI idle & fuel problems 10-27-05 09:24 AM - Post# 800798 In response to Kansas_Farmer I replaced the fuel filter, no change, I exchanged the IAC with the extra one that came with the truck and it exhibits the same symptoms. my 318 have big problem with Idle RPM and throttle response. Log in Register. Turn the screw to adjust the idle speed to 650 RPM +/- 50 RPM. Hi, Just joined but have been using these forums for a while for information. 7 liter TBI engine, HEI ignition with detached coil. here's a link to the part, Sprayed around the TB base gasket with WD 40 to check for surges in idle. There are no vacuum leaks I can find. 7L TBI surging idle, lacks powers and runs better with MAP unplugged (Topic#319979); Van Go Poster Posts: 68 Loc: Las Vegas, NV Reg: 01-06-15 Throttle relearn procedure/New battery/Won't Idle or Run. it just dies. Sometimes if I keep her running holding the throttle, after she warms up she will idle, but it will choke horribly trying to stay alive, and eventually die. Hello everybody, I am new to this site. I'm out of Ideas. The truck has new wires, cap/rotor, plugs. The surging continues throughout the RPM range. I've only had it out for a couple of drives long enough to get up to temp, but it adapter and gauge, but I have to say I'm extremely disappointed in it. U. The motor is out of an 88 1 ton pickup and is in a 89 1/2 ton suburban. New MAP, EGR, O2, TPS, ESC, distributor and coil. I have restored it and it is in very good condition mechanically and cosmetically. New posts Search forums. When it first fires up its at a fairly high rev, after about a This is a non chevelle question regarding my 87 burban with TBI. Sometimes the idle will creep up a few hundred rpm for a minute or two then back down. if it's more than that and won't come down, look for vacuum leaks or a mis adjusted throttle stop. So I set it to 0* and idle slowed down and ran smooth so I hooked the wire back up still ran smooth but when I shut the truck off and tried to restart it would fire up and die instantly. Hi, my wood truck, an 88 GMC custom deluxe won't idle or run worth a flip. So the issue I’m having is low idle. The engine seemed to run fine while driving. Click for thumbs down. Never mind it won’t allow me to attach a video. computer controlled 454. Anyway, I've had an erratic idle problem with our '89 K1500 5 speed since it had the bad motor in it. Thanks again for the help and guidance. I can keep it running by pumping the gas peddle, but if I let up it quits. -Russell 1990 Toyota Cressida 7MGE 3l I6/5-speed manual Post: TBI high idle (Topic#343846) dji Member Posts: 43 Loc: texas Reg: 05-21-03. 7 TBI (3 year old Jasper for 35 minutes, revving and idling finepulled it out to do a road test and revved a few times and blam, backfiring, won't idle. Have seen many complain that when they got the bike the idle was low, then later on the idle is too low and motor dies. I have had consistently high idle since I bought the truck in may. just stalls. Total 89 TBI 7. I have a 1999 305 chevy mercruiser, ser L619326, that will not idle properly. Runs great and has under 100k kilometres on it, but at idle it bogs down to a near Forums. best2011 has reacted to this post. Idling will not cause her to die though, only movement and shifting. Wait 5 minutes. Not sure what it is exactly, but sounds to me like around 1200 RPM. 7 TBI intermittent poor idle/slight misfire FusionBB™ Version 2. zip (0, 2 views) Stock. It will not fast idle. Try this test also, disconnect the vacuum line going to the EGR valve and see if it improves the idle. Your RPMs will drop way down the car may feel like it’s about to stall. New posts Latest activity. 7 long block in my '87 Chevy pickup. if it's warm, it won't idle on it's own. It feels like a misfire. 89 S10 4. Another thing to The truck idles erratically, and almost completely stalls while driving down the road. 7 TBI conversion 1978 Mustang II King Cobra Road Racer - Holley 650, MSD 6AL, 5 speed, After trying several other fixes I finally diagnosed and repaired the problem part. he is asleep right now or I'd ask him specifically what it was. This is just the tip of the iceberg. wont idle or start without priming tbi - Chevrolet 1992 K1500 question. 7, 2wd. Usually it wont do it in the mornings but after i have driven it to class and back a couple times it will start doing this. If y'all have any suggestions I'd be appreciative. 3 TBI VIN Z that runs way too rich. 7 GSi with TBI worked on by a shop here in San Diego (I wont mention any names yet) for oil pan replacement. Check Vacuum Lines for It's hard to get started and either won't idle on it's own or will seek up and down like in the video. Browse Categories Answer Questions . Rough idle, stalling and subpar performance might result from the idle surge and stumble issues. When I start it with the cold start, the RPM's stay low but previously it would warm 1986 S10 Durango Trim Extended Cab, 2WD, 2. Idle speed is now once again governed by the ECM, but your idle should be smooth and steady, approximately 600 rpm in Drive (for unmodified cars). Once started it will barely idle, it will hunt and sputter between 400-600 unless I hold down the gas. It does not jump forward forcefully or jerk it just idles down and then spits and shutters till it dies. Sometimes at idle it will die when you put it in gear, but once you get it going, it runs fine at idle. At the beginning of this summer, I tried raising the idle a little bit for more AC performance, not realizing that the IAC would just bring the idle back down. Chevy TBI Fast Idle. 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. Otherwise everything is fine. Those are next on my list. Now it's idling rough and stumbles a bit. Joe. The idle has been tricky on TPI models. Jump to Latest The truck runs good while driving it, but once I let off of the gas pedal, it wants to bog down and die. im not that good with motors and i need help i have replaced the map sensor and that didn't help. My engine stalls or almost stalls when I come down to an 20 to 50 idle air counts. 1043 posts · Joined 2003 Add to quote; Only show this user #1 · Jun 1, 2010. I put in a new TBI kit. I guess I've already thrown enough parts at the thing one more won't hurt but I really feel like this is throttle related somehow. iac is possible,try this first since its so common and let me i have a 1989 350 tbi i was driving it the other day and it wasted acting up had no power and ran Ruff got it home to look at it. If you don't have a heated place to do the repair, pull the distributor, and take it inside and warm up to room temp. The throttle hangs and won't return to idle when I left off the gas. 3L TBI runs won't idle well and runs rough FusionBB™ Version 2. If the min idle is to high it takes longer to idle down. I bought Dodge b250 few months ago, it's 1989 TBI 318 and I'm spending a lot of time trying to solve his puzzle. The brakes don't affect the idle, but the truck is very jumpy while at a stop sign/light, I just assumed that was normal with its age and all that torque. It's a 89 k1500 5. 94' Tbi 350 won't idle The 1988 - 1998 GMT400 Chevy & GMC Pickups Message Board Register or Log In To Also after it dies once the injectors will not spray fuel. I figure this has been discussed before but I haven’t found a definite answer, I’ve got a 1987 Chevrolet V20 with a 350 tbi paired to a sm465, and it idles around 2000 on a cold start and comes down to around 1200-1400, I’ve never got it to get below 1000. Amazing how reliable TBI’s are. It goes up and down and dies. My truck shot the IAC code and I replaced it but it's still shooting the code. It has a throttle body injection system. Thread starter Trigger_guard; Start date May 18, 2020; Took it down the road and runs about as bad as a tbi should. Reset the idle mixture screws to give the highest idle speed, and readjust idle speed if needed. After about 10 cycles it dies out, what I am assuming is the Idle control motor clicks 3 times and then all you hear is the radio and the heater lol. - Replaced the TBI base gasket. truck bogs down and stalls when put into gear. Power is good, front jumps right up and the throttle response is crisp. 454 tbi won't idle when warmed up The 1973 - 1987 Chevrolet & GMC Squarebody Pickups Message Board My guess is in the past I squirted some brake cleaner down into the IAC passage, and I may have ruined it. New fuel filter too - Ecogard from Amazon. When braking it's like the truck doesn't want to slow down. 3 v6 TBI Thank you so much. Help! 89 350 tbi won’t run with timing advance plugged in Reinstalled now and timed to 0 degrees without the timing advanced plugged in but now it won’t run with it plugged in. You say new fuel pressure regulator, did you check your pressure after that? It s/b 9 - 13 PSI (according to GM specs), at idle and under acceleration, preferably 11 - 13PSI. that keeps the engine from quitting when idling down,and IAC doesn't have to travel so far open. Like 2500 fast. Members. Check the idle air control it maybe restricting it. I have recently installed a new 5. Still idles pretty low and sometimes bogs down at idle and the engine dies. {post a question about tbi on a this board] I tried it again, this time bringing the engine up to running temp, Setting the timing to 0*, I did talk with Bryce today and even sent him some data logging. Replaced the IAC valve, re-calibrated the minimum air, Start the truck and see if you have the correct idle speed (425 plus or minus 25 RPM in drive and in Open loop. 89chevy4scrap; Apr 16, 2024; Engine Performance + Maintenance; 1989 Dodge D150 318ci TBI 2wd 1/2 ton Automatic Symptoms: Idle raises and lowers, after warming up. Dad's jeep runs an 87 350 tbi in his jeep with the same kinda problem. ASE, Username Post: 1990 5. When it first fires up its at a fairly high rev, after about a changing out the seems like forgotten idle air control on a chevy tbi I have a 91 Silverado K1500 4x4, 5. Attached Files Sniper_idle. Hi Chris. When I was having problems I bought a TBI rebuild kit but after I found the correct fuel pressure solved my problem I put that on the shelf. I had an assistant watch while I was pumping it and he said I had a lot of fuel while pumping, so I assume the TBO nozzle itself is clean. 1) wont idle, kind of lopes a little bit (not cause of a cam) stumbles n dies 2) When trying to give it fuel its like it drowns out, but as soon as u let off the throttle from trying to rev it and it stumbles, it revs up some, then dies down n trys to die. This could be related to the fire, or maybe not, I don't know. If it won't fully warm up, it'll never properly learn the idle. If so then I can confirm unplugging it makes no difference, the truck runs the same with or without that connector connected. IAC is good 0-5% most of the time. TPS 0. So, I shut it down and restarted it, and now it is running smooth again, but am back to the same high idle problem. But hardly anyone references the butterfly on the TBI unit not being adjusted right. These idle issues are sometimes hard to diagnose. It will start only if I hold down the gas pedal and feather it a bit. Doesn't do that any more yet if you put your foot to the floor in a gear where you should be down shifting, you can feel it surge a bit. gary. Customer: 1993 Chevy K1500 5. 1994 1500 5. O. It's got 20 hours on it. but it runs great when accelerating or about 60mph and faster almost like nothing is wrong with it. If I’m rolling to a stop and put it in I have a 1991 K2500 with the 5. About 10 seconds after the idle stabilizes, it stops spraying fuel from the injectors. For now he burns up starters Post: TBI high idle (Topic#343846) dji Member Posts: 43 Loc: texas Reg: 05-21-03. Re-connect the connector onto the IAC. Replaced cap, rotor, plugs, and On a cold start first thing in the morning it will crank fine but will not fire. 8 -> High idle. 7L TBI intermittently stumbles/stalls at idle, and frequently falls flat on acceleration down the road. I rode it up and down the street with the choke off. if adjusting the set screw doesn't bring idle down, you have a large vacuum leak somewhere. I had not started it in 4 days, so I turned the key back off(to reprime the tbi) and tried again. Will test the MAP sensor next. 44 Posts. Registered members Current visitors. Its a pain to We just want the engine to idle, if it is high that is ok until it warms up if it is low and wont idle go in a small amount on both screws until it will idle. Vehicle 305 TBI--starting hard, wont idle, dies when reved Vehicle was running fine, all of sudden died on road. it'll run like that for about 5 min. I am not getting as good of fuel economy as I think I should. 1988 w100 wont idle. it seems that the idle speed motor is not moving, it doesnt move when shutting the motor off through the same thing, replaced my idle speed motor, which was a waste of money (didn´t help). It has a pretty new napa reman motor w/~1,000 miles on it. It just dies every time you do anything but run down the road. My former boat was TBI and the idle was around 750, dropped to 650 in gear. When accelerating holding ur foot completely steady the engine (by sound and watching Tach) kind of varies up or down by about 100 RPM like it can't find a So I’ve got this issue with my tbi 350. Please login or register. Base gasket failure under the TBI is very common. If it doesn't come down, it may be suspect. My motor will stay at around 2500-2900 rpm's when I push the clutch to the floor. 7L TBI Here's a list of what I've done so far. No it's very easy to start after it dies it starts right back up and continues running ( with the rough idle ) I have looked down in the TBI and it looks like both injectors are squirting very well. The throttle body gasket had broken and was letting in too much air caus The GMC I am keeping because its in better overall shape. I did talk with Bryce today and even sent him some data logging. 4. I went for a drive and the pressure was steady at 13-14psi throughout the entire drive. Sometimes when it idles it will surge, sometimes not. It will start (on muffs) and run, and accelerate, but when I bring it down to idle, it may run a couple of seconds then die. Occasionally when starting the RPMs race up and down. Insert a T-30 size Torx driver into the Idle adjustment screw that is located behind the plug removed earlier. Execution time: 0. TBI idle problems. 4, 400 transmission. when its at a ideal it revs up and then right down and sounds like it going to die then ideals back up and so on. While driving the truck you have to fight the engine to stop the truck because the idle is so high and won't come down. And being that the engine had 300k miles on it I had it Readjust the idle speed to around 800 rpm or so, or to where you like it. We could get it to idle down to normal sometimes by holding the brake in all the way. Start the engine. I did replace the plug wires, cap rotor and coil, they all needed replacing pretty bad. Idles down low and just gives up. 3L TBI gas guzzler and an automatic trans. 89 Ramcharger 318 TBI cranks, no fire,no fuel,no power to coil,idle control etc Jump to Latest 8. 1989 Chevy K3500, 454 TBI, starts, runs rough, won't idle, no power, TBI just rebuilt. If it settles down, it could be the linkage. Again, no strong gas smell, but acts like it's flooded. like a race car or a harley. Picked up a 1988 K3500 last year with what I believe to be a TBI 350. Replaced plug wires, plugs, cap, rotor. When you start the truck it immediately goes to 1800-2000 rpms for several seconds before settling to idle at about 1100 rpm. Total Queries: 15 Zlib Post: '88 5. Also when ac kicks on it will idle down and stall. It is definitely running RITCH when it stumbles. I had my 2001 Striper with Volvo Penta 5. If I let the idle slow down and then give it gas, it bogs and dies. figure there is about 8-9 gal in the tank now. Lets start with the high idle. 07-09-2018, 10:29 PM. 454 TBI - Rough Idle / Stumbles MAP? Jump to Latest 13K views 7 replies 2 participants last post by Unstable Jun 3, 2010. Installed stock rebuilt engine a few weeks ago. Search Fixya Browse yea sounds like a belt or Chane but dose not jump going down the road much most of the time will do it when u start the car. KTM came out with recommendations to adjust the idle by adjusting the air screw on the throttle body (You end up opening the air screw a few turns). also you've checked to make sure that the temp. If the idle comes down then for some set of reasons the IAC isn't functioning which can be a failure of the computer to signal or for Re: high idle with tbi 350 08-23-06 05:35 PM - Post# 989935 In response to bowtie-badboy well i tryed the reset thing and i dont think it worked cause i herd no sounds . 8 TBI, automatic, 2WD with 122K miles. If you are holding the rpm down (below idle) while ecm is trying to increase it, then it makes sense that when the engine is freed idle would surge before dropping back to normal. When started cold the engine should start without pushing The engine is a tbi from heads up but has an older block. we drove it and if you are driving around 55 -80 if you let off the accelerator and put it in neutral the idle stays up, I have a 1994 z85 4x4 with the 4. 20 to 50 idle air counts. Cap & Rotor & Fuel Filter. then it smooths out and idles at around 1k rpm or slightly higher. When I time it by ear, it idles perfectly and revs although sometimes it Help! 89 350 tbi won’t run with timing advance plugged in Reinstalled now and timed to 0 degrees without the timing advanced plugged in but now it won’t run with it plugged in. I bought a new one and installed and its not working. If I stab the throttle it will then back down. here's a link to th 1990 Chevy 350 TBI wont idle. After trying several other fixes I finally diagnosed and repaired the problem part. LG . When I time it by ear, it idles perfectly and revs although sometimes it A friend got his 300 TPI delivered last week and was unhappy with the idle which was very low and erratic. when i give it throttle it wont take it. I keep thinking that I should rebuild a 25 year old TBI on principle but it runs so well I hate to mess with it. In gear it stalls out. My bike cant idle for more then 4 seconds without the cold start pulled. I just The other is me running down the road and driving through neighborhood next to me. Jun 17, 2012 • 1987 Toyota Had this problem for a few years now and finally I want to get to the bottom of it. I have a 1988 Chevrolet V30, 7. When the air conditioning is turned on, the engine will stumble and stall at idle while in gear. None. For those of you that are wondering why you are not getting Tahoes » 95 Suburban K2500 7. I have replaced the fuel filter and injectors as well as related wiring. Posts 41 Thanks 0 Location Central California and won't idle-it's not the fuel itself. It does this whenther the truck hot or cold, makes no difference. On startup it’s idles way to high and never really drops down. Then after ~5 seconds the idle smooths a little and comes back up to around 800rpm, but is still rough. System is going lean, and after 20-30 seconds of running lean, then goes into open loop forever. Now Im trying to correctly reset the Idle screw. TBI being a MAP sensor based system will see the leak just like opening the One out of five times the idle will seem to fall out when taking it out of gear and coming to a stop. I've replaced the TBI / manifold gasket you won't get the IAC to work properly unless you can get what's called MINIMUM AIRFLOW established and that won't happen if you have a bunch of air 1989 Chevy K3500, 454 TBI, starts, runs rough, won't idle, no power, TBI just rebuilt. Normally at idle it’s around 700 at cold start in park and it drops down to about 400 in gear and will sometimes drop and rise and even die. We changed every sensor without luck and have a theory it's in the distributor and is maybe worn wobbly. The motor seems very weak to me vs what it should be. This morning I changed the Fuel filter on the passenger side rail. Tags 350 chevy idle issue rebuild stock. SO I have an 88 YJ with the TBI. The only trouble code Never getting down to proper idle is likely a vacuum leak. Please Help! the initial shutting off and restarting after 10 minutes sure sounds like a pick up to me that doesnt explain why it wont idle, but a TPS would. Starts like a great. 4l (454) won't idle under 900 FusionBB™ Version 2. when cold, it will start and idle but pretty rough. I Don't have Ramcharger but decided to post here because I know you guys are knowledgeable about TBI I bought Dodge b250 few months ago, it's 1989 TBI 318 and I'm spending a lot of time trying to solve his puzzle. Already replaced the plug. Tags 350 chevrolet help idle truck. 5. Something new started happening when I drive the truck. this is most often caused by a vacuum leak. Also while driving down the road it'll cut in and out for a few seconds. After the timing adjustment I was able to get it to idle but it was mildly to moderately rough. Logged 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. The throttle body gasket had broken and was letting in too much air caus Moses, your website has been extremely useful for me while working on my 1989 Jeep YJ Wrangler 2. Last September I drove from Oregon through Cali down to Palm Springs and it was in the range of 3. The most common comment from an owner after a fuel pressure problem is fixed is "it has so There are various actions you can take to attempt and fix the problem if your TBI-equipped car exhibits idle surge and stumble. 04-07-17 07:05 AM - Post# 2685388 I did look down the IAC port but didn't see the pintle. Truck isn’t running rich, CEL is off but the idle is rough. I cannot even get it thirty feet before it shuts off. best2011. I dont think the Air/Fuel ratio is right, lacking air? Jeep idles high when started, goes down to normal idle, and once warmed up will idle rough and low, 600-700. With the new $5 gasket it purrs like a kitten. The engine is revving up and down when I come down to an idle. 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. no scan tool. I have a high idle problem. Like in a parking lot that kinda stuff. so i un screwed the IAC from the throttle body and jumped the pins (i think they were the right ones) and it didnt move at all, but my check engine light kept flashing one pause then twice , over Symptoms of a failing idle air control valve. The problem seems very closely linked to the actual physical position of the throttle Carburetted and TBI Injected '87 Omni won't idle. You let out on the clutch slightly and it dies unless you catch it with the throttle. I think that issue and the rough idle are the same thing. Hot start it most of the time won’t start unless I give it a little throttle. 9K views 14 replies 8 participants last post by v737d Oct 14, 2014 TBI idle adjustment. 3L auto. Thread starter neveridle; Start date Dec 4, 2013; When I brought it home I hooked the wires up to the 02 sensor and it was amazing, the motor quieted right down and ran much smoother. It got down to -12 last night so that didn't help anything. Typical TBI motor will idle with 20-21 inches of vacuum stock. Things I have done: Checked for injector operation. There is a large “sucking” sound coming from the throttle body when it is warmed up. 0 helpful. Problem is when I first start the truck in the morning (or after truck still wont runs smoothly from a cold the idle will come down on it's own after several minutes of high idle. right now, the dang thing won't idle at all. Jump to Latest Smear FRESH Epoxy down on the rivet points to eliminate the looseness. 7 TBI conversion 1978 Mustang II King Cobra Road Racer - Holley 650, MSD 6AL, 5 speed, Hello all, Recently bought a 91 crewcab square with a 454 TBI with a 4l80e behind it, after vehicle has been shut off, after more then 30 seconds it won't restart, found injectors to not be pulsing on startup/spraying fuel. A faulty idle air control (IAC) valve can cause a number of problems with your vehicle: 1. New used motor went in and the problem still existed but wasn't as frequent. Members idle air control valve could be sticking,take it out and clean the carbon off don't scrape the plunger thats the seat of the valve and don't like scratches. Have'n you along-Is like loose'n 2 good men. The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic If the chemicals get down inside the IAC, Also don't forget that these engines learn their idle. 87 idle surging/stalling issues. Got timing roughly set around 0. Bad Idle Air Control Valve. It will correct itself after about 5 seconds, can usually Yes, you need an adapter, but chances are good that your local auto parts store has what you need available on rental. I have read some really good posts so I am going to post one for some answers. Surging idle can be caused by a number of different problems. Giving you this slight history lesson so you know what I have done so far. Thank you for the feedback. You can reset the idle air control (IAC) valve by turning the car on, putting the car into park, pressing the brake down, then pushing the gas pedal down may not be suitable for all vehicles and components and you should only use these products if you are confident they won’t do any harm. once and a while it will stumble so bad it dies. Send Private Topic View Profile. Start engine. If I get it going and play with the throttle, I can keep it going, but it won't idle. No power loss or hesitation. S. Answered by Joe in 23 mins 15 years ago. Do not start replacing sensors and doing voltage and Replacing the fuel filter and the tank fixed that problem. drrgl kpevp cud ssebb kslfyz xpbqf wbcm czyyeg nyoi zdtad