Stalling when starting warm engine

[Clubguy]

Hello, I would appreciate some inputs before going fora repair on Friday.I have a 97 Camry, mint condition-tuned up great shape.
when cold, engine starts on a dime. For at least 6 months intermittantly when I would start the engine when warm or hot, The engine would start but immediately the RPM would drop to almost 0, almost stall then pop up again and idle normal. Well lately upon the same conditions the engine RPM will stay low for 5 seconds and sometimes WILL stall and I have to start it again then it is fine. I know there are idle control units that will adjust the idle for hot or cold conditions, Can anyone suggest what parts should be checked for this condition. Since it is intermittant I might have to take a shot in the dark for part replacement and would like to know if anyone has a best guess start.I was kind of thinking EGR I will be bringing it to Toyota dealer [as you know he will not like to spend a lot of time on an intermmitant condition. Any inputs appreciated.
Vince

[gelcol]

go check trouble shooting in haynes manual to auto zone or pep boys according to yr. model.

[ishop4less]

is the check engine light on? usually the computer will give u a signal if there is a trouble. If it does you need to have it read the code, then we go from there.

[GSS123]

Need to see if someone can pull a code. Some auto parts stores will provide the service at no charge. And your toyota dealer will usually do this service of a very reasonable charge. Then we'll have some place to start.

[Clubguy]

Hi,, No codes, no check light, nothing. dealer said he believes it is IAC valve but he cannot duplicate problem it it intermittant and that makes it tough.May not happen for a week. He will not replace IAC valve unless I take the responsibilty. All my research points toward IAC but it is expensive. Need a mechanics best guess opinon in here. I am going to replace but would like any other input that would suggest a better part to try first
D

[ishop4less]

Go buy carburator cleaner, open the air intake housing, clean it the air opening housing really good and the IAC valve most likely stick. After you clean it good, put everything back and start the car, by now the car really hard to start due to the left over spray from carburator clearner but eventually will start.

[Brian R.]

When you clean the intake, park it on an incline so that the passenger side of the car is higher than the driver's side. Then the carburetor cleaner will mostly run out of the intake (hopefully onto a rag).

[burchard]

Hope is no to late. Check the ECT (engine coolant temp) sensor. With a cold engine let it idlle to warm up. Watch the rpms. They should go to 1000-1500 and the when is warm up go back to 750-800. If you see at some point the rpms going up and downs erratically when is warm up you maight have a defective tem sensor. If that happens disconecct the temp sensor and see if the rpms stabilize.

Anothert way to check this is to connect the temp sensor to a voltimeter and read the resistance which should decrease with increasing engine temp. If you get increases in resistance readings with increase in temp, your temp sensor is gone.

Additionally, if you get a warm stall, open de hood, disconect the temp sensor and see if you can start the car. If you can start it it again once the temp sensor is disconected, it could be a defective temp sensor. Never drive with the temp sensor disconnected.

other posibility is a dirty EGR.

good luck

[Clubguy]

When engine is running idle is perfect. this problem only happens at start up warm or cold. Lately it has also happened at a cold start up. I know it is not the cold injector because engine does start. If it was a cold injector problem, engine would only crank. when symptom occures it is at start up, idle goes very low for about 5 or 10 seconds engine shakes a little, then RPM will usually come back up to normal. almost like idle controller is sticking closed. idle does not fluctuate eractically.
You would think there would be some way to test , but my dealer said if it does not actually happen in shop he can't really 100% diagnose.


C

[burchard]

Originally Posted by Clubguy

When engine is running idle is perfect. this problem only happens at start up warm or cold. Lately it has also happened at a cold start up. I know it is not the cold injector because engine does start. If it was a cold injector problem, engine would only crank. when symptom occures it is at start up, idle goes very low for about 5 or 10 seconds engine shakes a little, then RPM will usually come back up to normal. almost like idle controller is sticking closed. idle does not fluctuate eractically.
You would think there would be some way to test , but my dealer said if it does not actually happen in shop he can't really 100% diagnose.


C

It might be your AIC valve (Air intake control) that is sticky. Check this post:

http://www.automotiveforums.com/vbul...r+intake+valve