Thanks! Did your GTP idle roughly? Also, did your problem only occur during the summer time (or when the temp is greater than 70) or did the problem exist at any outside temp?
Alex
Alex, when I first bought the car, it had a problem when you first started the car in the morning…idle would be very erratic and go up and down until the car warmed up to operating temperature…this was due to a leak in the air intake manifold gasket…when I replaced it there were no more problems…now, as for the EGR problem, it would not die on me when I wanted it to for others to see…I thought at first temperature had something to do with it, it would die at red lights, it would cut-out going down the road, started when it felt like it, and so on and so on…so, the answer is yes but not always…it had a mind of its own meaning it would run great for a few days or a week, then out of the blue go crazy on me…and yes, it was during the summer time, but happened in the morning, during the day, or night, just whenever it felt like it…then you must also consider I live in Texas where it usually is above 70 anyway…did you locate the EGR valve and already clean it? Later…James
Hi James. OK, well I unbolted the EGR valve and cleaned it. I didn’t see much carbon build up, but the “thing” moved vertically a little smoother after cleaing. I’ll let you know what happens.
Thanks!
Alex
Car stalled out 2x today after cleaning the EGR valve. 
I have a 1999 Pontiac Grand Prix GT that while driving would lose power then suddenly pick back up sporadically.The check engine light was on so I took it to Advanced auto to have a the codes read, the error code translated into the airflow sensor being bad.I purchased a remanufactured one for approx. $145.00.I put it on this morning and have driven the car all day without further problems-Hope this helps someone!!
I’m sorry that cleaning the EGR passage didn’t fix the problem but I could have told you that it wouldn’t.
A plugged EGR passage will not cause the car to stall… period. I dont care what anyone says, it can’t happen.
An EGR valve that is stuck open at idle could cause the car to stall but it will also have a check engine light on and set a code for the EGR valve.
As I said earlier in this thread you are going to have to check the basics… is there spark and fuel?
I left the car with the mechanic for 2.5 days. They were able to observe the intermittent problem during that time.
They replaced the crank sensor and the fuel pump relay. So far so good.
Alex