Engine stalls at idle

Tiny
RUSTY DECKARD
  • MEMBER
  • 1994 CHEVROLET TRUCK
  • 5.7L
  • V8
  • 4WD
  • AUTOMATIC
  • 50,000 MILES
My truck runs great at idle but soon as you put it in gear it tries to shut off. I can push the gas down enough that it will stay running but coming to a stop while pushing on the brake it isles down really low starts to lurch with the brake applied then will shut off. This only happens when it is colder then thirty five degrees outside which is a lot in Alaska. I have replaced the distributor, cap, plugs, wires, ten injectors and injector wires, IAC, TPS, pressure regulator. Still all with no change.
Tuesday, October 24th, 2017 AT 10:30 AM

30 Replies

Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 42,870 POSTS
This sounds more like a transmission torque converter locked up, do me favor when you are coming to a stop slip it in neutral to see if the engine stalls. If not, out it back into gear, if it stalls you have your problem figured out.

It also can be a vacuum leak at the throttle body which is have seen before lets run down this guide for me please.

https://www.2carpros.com/articles/stall-at-idle

Please let us know what you find.

Cheers, Ken
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Wednesday, October 25th, 2017 AT 7:15 PM
Tiny
REY-GTS
  • MEMBER
  • 1 POST
Yep I had this program not in Alaska though lol. I had to replace the IAC motor all fixed! I love this site.
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Saturday, September 29th, 2018 AT 6:13 PM
Tiny
STEVEW/94
  • MEMBER
  • 3 POSTS
  • 1994 CHEVROLET TRUCK
  • V8
  • 4WD
  • AUTOMATIC
  • 185,000 MILES
I have checked and replaced fuel pump, regulator injectors, oxy, map, coolant, knock sensors, did a valve job and replaced distributor, coil, plugs and wires and ECM. Truck will not idle unless map or coolant sensor disconnected. Fuel has 15lbs and plenty of volume bur engine is lean, lean lean. Any suggestions?
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Wednesday, November 25th, 2020 AT 8:16 AM (Merged)
Tiny
DOCFIXIT
  • MECHANIC
  • 18,828 POSTS
The fuel pressure is to low it should be @42psi Please look at this guide it will help us.

https://www.2carpros.com/articles/stall-at-idle

Please run down this guide and report back.
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Wednesday, November 25th, 2020 AT 8:16 AM (Merged)
Tiny
STEVEW/94
  • MEMBER
  • 3 POSTS
All my specs say 9-13 lbs
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Wednesday, November 25th, 2020 AT 8:16 AM (Merged)
Tiny
DOCFIXIT
  • MECHANIC
  • 18,828 POSTS
My bad thought 94 went to EFI so you are throttle body. Get your timming light hook up run truck point light at injector to see spray pattern. Should be no drips and 360 deg pattern. If not inj fouling and causing lean. Also rev up make suer both are functioning.
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Wednesday, November 25th, 2020 AT 8:16 AM (Merged)
Tiny
STEVEW/94
  • MEMBER
  • 3 POSTS
My timing is right on and I have installed new injectors with full 360 deg spray (checked and double checked that injectors are correct size) Installed all new O-rings so I have no drips. Cleaned IPS and IAC today with no change. It will not idle when cold, it dies and even if throttle is held to 2000rpm is still dies. After warm up it idles. But choppy. Im thinking about changing throttle body and installing adjustable pressure regulator. What do you think?
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Wednesday, November 25th, 2020 AT 8:16 AM (Merged)
Tiny
BOBBY71
  • MEMBER
  • 13 POSTS
How is the vacum? Check egr out. May be stuck open! Or egr valve diafram broken put vacum pump on it see if it holds. And check vacum lines. Before spendind anymore money
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Wednesday, November 25th, 2020 AT 8:16 AM (Merged)
Tiny
SHERILUMINA
  • MEMBER
  • 1 POST
  • 1992 CHEVROLET TRUCK
My car has been stalling when I am at a stop sign, lights or basically whenever your foot is not on the gas pedal. The fuel system has been tested and is fine, we changed the spark plugs which seemed to fix the problem for 2 days, then it happens again. Sometimes the car runs fine, other times it does not. If I have to take my foot off the gas I have to put it in park and rev the engine to keep it from stalling. It starts fine, turns over decently, sometimes acts up when im turning it over but it always starts. Engine revs good, but as soon as you come to a stop it usually stallls out. Someone said it might be the Mass Airflow Censor, but then I read my car doesnt have one. Any suggestions? Thanx
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Wednesday, November 25th, 2020 AT 8:16 AM (Merged)
Tiny
N2K3L
  • MEMBER
  • 1 POST
Maybe check the IAC valve. From what you described I believe that is a common problem with these cars.
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Wednesday, November 25th, 2020 AT 8:16 AM (Merged)
Tiny
FIREFIGHTER EARL
  • MEMBER
  • 2 POSTS
It is your computer that could be causing that problem because I have the same kind of car and I got a new computer from NAPA and I put it in the same day and so far I have put 20,000 miles after that. So talk to your local NAPA and get one it only cost about 1 or 2 hundred dollars and it should be on the passanger side under the coolant container
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Wednesday, November 25th, 2020 AT 8:16 AM (Merged)
Tiny
WAYNEL
  • MEMBER
  • 1 POST
  • 1992 CHEVROLET TRUCK
My truck will start for approx. 10 seconds then stalls, it will do it for about 10 times, then it will run with no problems. This doesn't happen all the time, it usually happens in the mornings, however it has happened when the truck was warm. Can you please help!
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Wednesday, November 25th, 2020 AT 8:17 AM (Merged)
Tiny
MERLIN2021
  • MECHANIC
  • 17,250 POSTS
Lets start with a fresh tune up? How long ago? Then make sure the fuel pump can pass muster. New air and fuel filters? Hard start is most always tune up related.
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Wednesday, November 25th, 2020 AT 8:17 AM (Merged)
Tiny
MERLIN2021
  • MECHANIC
  • 17,250 POSTS
Ok the next step is to look for vacuum leaks, get a can of spray gumout, and start spraying the vacuum hoses and manifold, When the engine changes speed, you have located a leak.
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Wednesday, November 25th, 2020 AT 8:17 AM (Merged)
Tiny
RANDERSON3991
  • MEMBER
  • 1 POST
  • 1991 CHEVROLET TRUCK
  • 24,400 MILES
My 1991 chevy silverado wont idle. It idles when cold but when it warms up it wont idle when you put it in gear or come to a slow down or stop. I have replaced the IAC, coolant temp. Switch, worked on the EGR, fuel filter, cap, rotor, wires and plugs. Have checked everything I can think of, need help
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Wednesday, November 25th, 2020 AT 8:17 AM (Merged)
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
Common for the gasket under the throttle body to leak vacuum and cause stalling. See if it is broken or cracked.

Roy
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Wednesday, November 25th, 2020 AT 8:17 AM (Merged)
Tiny
NDBURBANK
  • MEMBER
  • 1 POST
  • 1991 CHEVROLET TRUCK
  • V8
  • 4WD
  • AUTOMATIC
  • 225,000 MILES
We cant seem to get my 91 to idle. I had this problem beofre I had the new motor put in it. And now the mechanic working on it cant seem to figure it out either. I did a bascic tune up on it a couple months ago and all was good. Then all of sudden this idling problem comes. The only reason we changed motors was milage and it was starting to smoke ike I said it had this problem before we swaped motors. And we've already redone the intake gaskets on the new motor
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Wednesday, November 25th, 2020 AT 8:17 AM (Merged)
Tiny
2CARPRO JACK
  • MECHANIC
  • 11,533 POSTS
Could be a stuck Idle Air Control Valve. If you remove it from the TBI, plugged in, when the key is turned on it should go in them out. If not it isnt working
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Wednesday, November 25th, 2020 AT 8:17 AM (Merged)
Tiny
CHRISTINA SAYRE
  • MEMBER
  • 1 POST
  • 1991 CHEVROLET TRUCK
Blazer shakes and stalls when at idle and drive replaced c. Converter plugs and coil what next?
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Wednesday, November 25th, 2020 AT 8:17 AM (Merged)
Tiny
LOSONE
  • MECHANIC
  • 1,616 POSTS
Sounds like a vacuum leak or a bad idle air controller. Have you checked the obvious like wires, plugs, distributer cap and rotor? The power brake booster is often a source of a vacuum leak. Good luck
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Wednesday, November 25th, 2020 AT 8:17 AM (Merged)

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