Idling problem w/ 1988 Grand Prix

Ok, I just replaced the EGR valve because it failed emissions. Immidiately after this, the idle on my car went to crap. In park, it is fine for the most part. In nuetral, it is fine, but put it in drive or reverse and the thing conks out all the time. Driving at normal/ speeds is fine. Only when I come to a stop sign does it have trouble. I have to throw it in nuetral so it doesnt shut off. Could this be the PCV valve? What should I do?

Also, is there a way to obtain trouble codes from the car?

What size engine and have you gotten to the point where the torque convertor has locked up? The PCV can cause idle problems if it is bad and it is a cheap replacement. If the car is fuel injected remove idle air control motor and throttle body and clean them thoroughly with throttle body cleaner. You will probably find that the car will run and idle much better.

Thank you for the tip. Engine is 2.8L

What size engine and have you gotten to the point where the torque convertor has locked up? The PCV can cause idle problems if it is bad and it is a cheap replacement. If the car is fuel injected remove idle air control motor and throttle body and clean them thoroughly with throttle body cleaner. You will probably find that the car will run and idle much better.


How do i know if the torque converter has locked up?

The convertor will lock automatically at around 45 to 50 mph. You may feel like it switches to another gear when it does so. In the transmission there is a solenoid located on the end of the transmission (drivers side) that causes this to happen. If it goes bad and it will routinely especially as the mileage goes up, it will not unlock properly causing the car to stall. If you unplug the solenoid, plug on top of the transmission, then the convertor will not lock up. Usually the first sign of this is the car will stall when approaching a stop sign or will not move when put in reverse or drive. If you unplug the convertor solenoid then this will not happen. Does nothing to the transmission other than it will decrease your gas mileage. It can be replaced for about $50 along with a jack stand and a couple of hand tools.

I replaced the PCV valve and it is still stalling. I will replace the air idle control first, then maybe focus on the converter