Recently bought an '05 Grand Prix GT with 126,000 miles. It really is a clean car. Had the tranny pan dropped (pretty dirty) and completely cleaned out during flush and also had some other preventive maintenance done. A few weeks later had the throttle control module replaced because when starting the car would just die after the engine turned over. Once that repair was done my mechanic called and said the car started and ran great (he drove it 30 minutes). When driving the car home after the control module was replaced all of a sudden the car began shifting extremely hard with very little power to accelerate. The entire car would jerk when it shifted. Pulled off to a side street and the same continued until I got home. My mechanic (who is a high school classmate and has been in the business 31 years) came over to my house because he was bewildered and actually gives a darn and got in the car, stated it and it ran like a champ. His idea was maybe something had got sucked up into the mass air flow sensor while I was driving home but that is almost impossible he said.... The car then ran perfectly for a month. Then in the last couple weeks, randomly the same hard shifting will happen but not as extreme? My 16 year old son is driving it so he isn't too mechanically inclined but I worry about his safety. I told him when the car acts up, pull off the road, shut it off and restart it. When he does that it runs fine again! Any ideas????
Originally Posted by Jerry 05
