Car still stalling at idle

Tiny
GLENN GILBERT
  • MEMBER
  • 1997 DODGE AVENGER
  • 2.5L
  • V6
  • 2WD
  • AUTOMATIC
  • 150,000 MILES
I have the car listed above it is the ES model (easy miles on it). My problem which I simply cannot find an answer for is why the car continues to stall at idle when warm or cold. I had an engine light on and pulled a code for a bad oxygen sensor which I replaced. After I replaced it the vehicle started quicker and ran better but then started stalling again. I do not have an engine light on so I cannot pull any codes now. I am running out of ideas on what else could be causing the stalling. The car starts right back up when it stalls but you can tell the idle is just not high enough right now to keep the car running when at idle. What else may be the problem?
Friday, April 27th, 2018 AT 10:09 AM

6 Replies

Tiny
WRENCHTECH
  • MECHANIC
  • 20,761 POSTS
First eliminate all vacuum or air leaks in the system (very important)

You may have a bad IAC (idle air control) but try cleaning the throttle body first. Remove the intake snorkel, have someone hold the throttle wide open for you and scrub the back side of the throttle plate and surrounding bore with an old tooth brush and some carburetor cleaner. Be sure to spray some into the small holes next to the throttle plate. That should help stabilize the idle. If it still has a problem, replace the IAC.
Was this
answer
helpful?
Yes
No
Friday, April 27th, 2018 AT 11:56 AM
Tiny
GLENN GILBERT
  • MEMBER
  • 44 POSTS
I read on your website from another person with the same car and someone suggested a bad EGR valve. Could that possibly be the problem. I have been having this problem for a while and really need to see what is going on as my wife is getting scared to drive the car thinking it is going to leave her stranded. It will start right back up but sometimes at idle it will just stall when you are stopped and sometimes while driving it will surge or buck from time to time. If you feel cleaning the throttle plate will do it I will do it again.
Was this
answer
helpful?
Yes
No
Friday, April 27th, 2018 AT 12:08 PM
Tiny
STEVE W.
  • MECHANIC
  • 15,233 POSTS
I would start with checking all the vacuum lines for breaks/cracks, these are a speed density system that uses the MAP for a primary control signal so even a small vacuum leak can cause trouble.
Next clean the throttle body. They build up carbon around the throttle blade and block the idle air. Be sure you use throttle body safe cleaner.
Was this
answer
helpful?
Yes
No
Friday, April 27th, 2018 AT 12:20 PM
Tiny
WRENCHTECH
  • MECHANIC
  • 20,761 POSTS
Yes, a stuck open EGR can cause issues with idle but that is easy enough the remove and inspect. That would not effect anything but idle.
Was this
answer
helpful?
Yes
No
Friday, April 27th, 2018 AT 12:25 PM
Tiny
GLENN GILBERT
  • MEMBER
  • 44 POSTS
I cleaned the throttle body and it was dirty but when I took the car up to the corner it stalled almost every time I stoppled and the engine surged when I accelerated a few times. This is what I have done so far to give you a complete history of what is going on.
When I first started having this problem I also noticed that the engine temperature gauge started going up past halfway, which is normally does not do, and the engine fans kicked on. After taking it to my local mechanic they told me the radiator was half plugged. I changed the radiator and put a new thermostat in but noticed no antifreeze came out of the lower hose when I was changing the thermostat. After I put the new radiator and thermostat in the car temperature is where it should be at halfway on the gauge. The only problem I have with the cooling system now is that the heater blows cool air and no heat.

What I have done to try to fix the problem with the engine stalling and surging is I replaced the ASD relay and TPS switch besides cleaning the throttle body. When the engine light came on I had the code read and was told 1 of my O2 sensors were bad, bank 2 sensor 2. I replaced the O2 sensor and found a piece of what looked like asbestos on the sensor. After I replaced the sensor the light in the dash has not come on but the stalling and surging continues. If it is the EGR valve, where would I find it and what are the chances it is bad? I am running out of ideas on what could possibly be going on with this car. It is a 1997 Avenger ES 2.5 engine with 150,000 easy miles on it and I do almost all of the maintenance on the car but this one has me stumped.

Thanks
Was this
answer
helpful?
Yes
No
Saturday, April 28th, 2018 AT 10:08 AM
Tiny
STEVE W.
  • MECHANIC
  • 15,233 POSTS
No heat indicates an air pocket in the cooling system or a plugged heater core. For that I would try a core flush and an engine flush (done as individual pieces so you don't flush more crud into the heater core).

As for the EGR valve, There are a couple parts. The EGR control solenoid is on the rear of the engine between the intake manifold and the firewall. The EGR valve itself is just below the solenoid.

To test the EGR valve - remove it. Check to see if it is fully closed. If not and there is no carbon blocking it, replace it.
If it is closed then use a vacuum pump with a gauge on it (the small mityvac hand pumped style)
Apply 20" of vacuum and watch the gauge. If it starts to drop replace the valve as the diaphragm is bad.

Now apply a slight vacuum to the valve, 2-2.5" and blow into one of the ports. Air should not come out the other port.
Now apply 6-7" of vacuum and check airflow again. It should flow this time as the pintle valve is lifted off the seat.
Images (Click to make bigger)
Thumb
Thumb
Thumb
Was this
answer
helpful?
Yes
No
Monday, April 30th, 2018 AT 8:03 AM

Please login or register to post a reply.

Related Engine Stall At Idle Content

Engine Stalls After Dead or New Battery
GUIDE
Engine Stalls After Dead or New Battery
So you installed a new battery and now the engine stalls? You have done nothing wrong because believe it or not this is normal. The engine computer has a learning cycle...
VIEW MORE