Car stalls at idle when engine is warmed up

Tiny
RLBUTTA16
  • MEMBER
  • 1999 SATURN SL2
  • 1.9L
  • 4 CYL
  • 2WD
  • AUTOMATIC
  • 218,000 MILES
My car drives fine in the city and on the highway. When the engine is cold or cool it will idle normally around 800-1000 rpms. Once the engine is warmed up to near the half mark on the temp gauge in the dash the car will stall or try to stall if idling for one minute to five minutes. The rpm's will drop to 500-800, engine will shake, and either stall out or surge up to 1300 rpm's before going back down to 1000. When the rpm's are low if I press the gas nothing happens or the car stalls out immediately. This only happens once it is warmed up. I have consistently let it idle for fifteen to twenty minutes when cold and no problems. Sometimes I get a very light white-grey smoke from exhaust for a couple of minutes. A quick note it always starts right back up after stalling.

This has been going on for a couple months. I am getting no error codes. Short list of things I have tried:

Replaced Camshaft Position Sensor.
Replaced Throttle Position Sensor.
Replaced Battery.
Replaced IAC Valve.
Replaced Spark Plugs (one had a little oil on it).
Cleaned Throttle Body.
Replaced PCV Valve hose.
Cleaned EGR Valve (had a fair amount of carbon build-up).
Transmission fluid level is good.
Replaced Air Filter.
Oil level is good.
Coolant level is good.
No fluid leaks.

https://www.youtube.com/watch?v=ZBRD8T7Mvv0 I made a ninety second video of me being in park once the engine is warmed up where I am just watching it, not pressing the gas or anything.
Do you
have the same problem?
Yes
No
Tuesday, June 27th, 2017 AT 7:04 AM

9 Replies

Tiny
RLBUTTA16
  • MEMBER
Today I replaced the fuel filter and will be making a trip into town that should get it warmed it. I will post my results when I get home.
Was this
answer
helpful?
Yes
No
+1
Tuesday, June 27th, 2017 AT 11:15 AM
Tiny
RLBUTTA16
  • MEMBER
New fuel filter did not fix the problem.
Was this
answer
helpful?
Yes
No
Tuesday, June 27th, 2017 AT 1:50 PM
Tiny
RLBUTTA16
  • MEMBER
Tonight I replaced the engine coolant temperature sensor, I will not know if that fixed it until I get home from work tomorrow since this problem only happens once the engine is warmed up. I will post results here.
Was this
answer
helpful?
Yes
No
Tuesday, June 27th, 2017 AT 8:49 PM
Tiny
KEN
  • ADMIN
Hello,

That is exactly what I was going to suggest.

Here is a guide that will show you what you are in for when doing the job.

https://www.2carpros.com/articles/coolant-temperature-sensor-cts-replacement

Here is a diagram of where its at on your car. (below)

Great job on the video BTW

Please let us know what happens, we are interested to see what it is.

Cheers, Ken
Was this
answer
helpful?
Yes
No
+1
Friday, June 30th, 2017 AT 12:05 PM
Tiny
RLBUTTA16
  • MEMBER
Seemed fine for 2 days but today as I sat in my driveway after a 25 mile drive from work it tried to stutter again while sitting in park. It didn't stall out it caught itself after maybe 10-15 seconds and revved up to 1500 rpms from the low point of about 700. It took 10 minutes or so of idling for that to happen, the temp gauge stayed a little over halfway between the 1/4 mark and the 1/2 mark, never hit the 1/2 mark. The engine was shaking pretty strongly so when I'm off next I'm going to replace the lower engine mount that's near the bottom on the passenger side. I'm running out of ideas.
Was this
answer
helpful?
Yes
No
Friday, June 30th, 2017 AT 7:17 PM
Tiny
RLBUTTA16
  • MEMBER
Sat for a few minutes in drive with my foot on the brake and the temperate at the 1/4th mark with no problems. Switched it into park and took my foot off the brake and within 20 seconds it stuttered out and stalled. Maybe I solved one problem but not the main problem? I'm so confused.
Was this
answer
helpful?
Yes
No
Friday, June 30th, 2017 AT 8:41 PM
Tiny
KEN
  • ADMIN
Hmm, it sounds lie you may have a vacuum leak causing the problem.

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

Please run this test and get back to us we are interested to see what it is.

Cheers, Ken
Was this
answer
helpful?
Yes
No
+1
Sunday, July 2nd, 2017 AT 6:37 PM
Tiny
RLBUTTA16
  • MEMBER
Will have to try taking it in this week for a true diagnostic then. I recleaned the EGR valve, where it connects to on the engine, the throttle body, where the throttle body connects in. It's stalling out in Park even when its not all way warmed up. Haven't had it do it in Drive yet but I haven't driven it around much either. I guess I could try cleaning the MAP sensor area in the meantime?

For the record I've tried spraying carb cleaner around all the vacuum hoses I could find and it didn't adjust the idle at all, I read that was a cheap way to test for leaks. Might give that another try too since I still have a can.
Was this
answer
helpful?
Yes
No
Tuesday, July 4th, 2017 AT 6:17 PM
Tiny
KEN
  • ADMIN
Yep the MAF is where I was going next, here is a guide that will help you clean the MAF but cleaning it doesn't always work and it must be replaced.

https://www.2carpros.com/articles/mass-air-flow-service

and

https://www.2carpros.com/articles/how-to-replace-a-mass-air-flow-sensor-maf

Please let us know what happens, we are interested to see what it is.

Cheers, Ken

Was this
answer
helpful?
Yes
No
+1
Wednesday, July 5th, 2017 AT 6:02 PM

Please login or register to post a reply.

Recommended Guides