okay... 2002 grand prix gt 40th anniversary edition....Originally Posted by Logan541
120,800 miles... recently straight piped with u- bend delete and no catalytic converter. installed new 02 sensor. recently did trans pan drop service.... but unfortunately, the quick lube place only used dexron 3 instead of dexron 6....
The car is throwing MANY codes including p1811... for a while it drove fine, then it started a very mild hard shift.
hence the reason for the pan drop service ... the car is now doing all sorts of crazy stuff including...
1. stalling as soon as you put it in park
2. rpms fluctuate when put in park from 200 rpms to about 1200 rpms.. then stalls.
3. throwing the p1811 code... and now shifting hard again
3.5 also throws a code for Throttle Position Sensor....
4. there was a dreaded moaning noise coming from what sounded like the trans in about second-third gear... while in gear at 40 mph.
HELP!
