Questions and Answers
Grand Prix P0742 Code
Q. I have a 1998 Grand Prix GTP with 75,000 miles on it. Recently I have been experiencing a problem which happens normally after the car is driven 200 miles. The check engine light will come on and the slow speed response is very rough like the engine is about to stall.
This has happened several times and I have not been able to get it to do it while at the dealer. Today I went to the parts store and bought a code scanner but the check engine light had went off. I connected the scanner anyway and retrieved code P0742 which says something about the torque converter solenoid being stuck. Does this make sense and is there anything you could point to that would help me solve this problem?
A. Gee, a GM product with a stuck TCC solenoid, how rare. Actually this is very common on GM vehicles. You would think after ten years of problems with it, they would have come up with a better way of controlling the lockup torque converter.
It seems like it is just sticking intermittently so I would suggest a transmission fluid and filter change to see if the clean fluid will clean out the TCC solenoid. If not, it will have to be replaced.
My article, Diagnosing GM Converter Lock-Up Problems explains this problem and how to diagnosis it.
Additional Information provided courtesy of ALLDATA