engines dies when stopping in the cold

Hello. I own a 1995 Saturn SL2 with about 90,000 miles on it. I have a
problem with my car when its cold outside. I have no problem starting
the car, and it idles fine. Except that if I rev up the engine and
then try to let it drop back to idle, it will go right past and the
engine dies. If I rev it up but let it slowly come back down to around
1000, then i can dtop giving it gas usually without dieing. This is a
major problem when driving because when i come to a stop and take my
foot off of the gas to break, if i push in the clutch as well the
engine dies. To compensate for now, I have been engine-decelerating
and then using the e-brake to come to the complete stop. Does anybody
have any idea why my car might have problems returning to idle in the
cold, but not maintaining idle once its there? If you have idea or
suggestions all are most appreciated. Thanks

- Brandon Kilgore

 

Dunno the cause, but I got real adept at pop-starting my old Corvair
when it did that. Usually once it was restarted it would idle fine.

 

Yeah, sometimes I forget to be careful with the idle and it starts to
die, and sometimes i can recover it either by flooring the gas or
popping the clutch, but either way it still dies the next time. In
fact there doesn't seem to be any correlation even between warming it
up and the engine being nicer, because even just this morning, i drove
the car for about 5 minutes with no problems, I didn't have to try to
keep it alive at all. THen I parked it for about 20 minutes and when I
got back in, the first time i came to a stop i expected it to be fine
like it had been earlier but it died.

- Brandon

 

I'm guessing there's something wrong with an engine temperature sensor.

 

Coolant temperature sensor is a common failure item on the 1.9L engine, and
could potentially cause this. Some of them have a tendency to crack and
corrode, giving a false temperature reading.

 

Thanks, I'll have that checked out tomorrow.

 

This is a

I have had the same problem with my 97
SC2. It has an automatic trans. I don`t know if my solution will help you.
Had the exact problems when cold. The car would start fine and when I would
rev it up and just let it go back to idle it would die. If I kept my foot on
the gas to keep it from dropping to zero I could keep it running.
Almost at every stop it would die.....sometimes it would almost die and just
recover and go to the normal idle speed.
In my case it was the pcv valve. In the cold weather it clogs up with ? a
white and brown substance. A mechanic told me that saturns have this problem
with their pcv valves in the winter. I replaced my pvc valve with a new one and
the problem came back even faster. Then I just cleaned out the old one with
carb. cleaner and replaced it and the problem was gone.
Every once in awhile I just take it out and clean it again. Hope this helps.
Dan.

 

Sounds like your plugs are coated. When was the last time they were
replaced?
Joe
Joe

 

|> Hello. I own a 1995 Saturn SL2 with about 90,000 miles on it. I have a
|> problem with my car when its cold outside. I have no problem starting
|> the car, and it idles fine. Except that if I rev up the engine and
|> then try to let it drop back to idle, it will go right past and the
|> engine dies. If I rev it up but let it slowly come back down to around
|> 1000, then i can dtop giving it gas usually without dieing. This is a
|> major problem when driving because when i come to a stop and take my
|> foot off of the gas to break, if i push in the clutch as well the
|> engine dies. To compensate for now, I have been engine-decelerating
|> and then using the e-brake to come to the complete stop. Does anybody
|> have any idea why my car might have problems returning to idle in the
|> cold, but not maintaining idle once its there? If you have idea or
|> suggestions all are most appreciated. Thanks

Here is yet another suggestion:

I am not sure if this applies to your engine, but in many cars, like
my 3.0L Voyager, the throttle plate gets dirty and closes off the minimum
opening that should exist at idle. Cleaning the throttle plate and
adjacent walls in the throttle bore restores the air flow needed at
idle. Stalling when stopping at intersections is the classic symptom
of this problem.

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Ned Forrester 508-289-2226
Applied Ocean Physics and Engineering Dept.
Oceanographic Systems Lab http://adcp.whoi.edu/
Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA