2001 Pontiac Grand Am SE 4-door sedan, automatic transmission, 2.4L 4-cylinder inline, front-wheel drive, 146000 miles.
The issue:
- “Trac Off” light will come on seemingly at random. No other light will come on; the “Service Engine Soon” and “ABS” lights stay off. Cruise control does not work while the light is on. Also it can no longer accelerate to top speeds; I can floor the gas pedal and it will just sit at ~2200 RPM and 72 MPH. It also seems to shift more violently and idle less steadily. Turning the car off and restarting resets the light, and everything including cruise control works normally again.
- Had a store scan the codes right after it happened one time and it read:
–C1275 “Powertrain Control System Requested ETS To Be Disabled”
–P0122 “Throttle / Pedal Position Sensor A Circuit Low Input”
–P0302 “Cylinder 2 Misfire Detected”
–Scanning the computer after it didn’t happen read the P0122 and P0302 codes but not the C1275 code. - It has happened most often on the highway while using cruise control, but has also happened on city streets and while not using cruise control.
- Nothing consistent seems to cause it and infrequent. When it does happen it tends to happen again within the same trip/day. Usually it takes at least 15-20min driving before it happens for the first time within a trip. I took the car to a mechanic one day and they couldn’t troubleshoot it because the malfunction wouldn’t even happen for them from only driving on city streets.
- For example, I drove from Chicago to Milwaukee and it happened a couple of times. Two days later I drove back to Chicago and manually turned the ETS off (ETS button the dash) and had no trouble. Then I drove Chicago to NYC and it did not happen until going up the hills in Pennsylvania.
Car otherwise runs well for its age and there are no issues while driving except when this occurs. I first noticed it occuring in the middle of last winter (I did not drive it most of the summer due to travel). I’m worried that this could indicate a larger problem. Could it be a sensor issue? A wiring issue? Or something wrong with the transmission?
I am also concerned that this could be safety issue in the winter if a ETS malfunction would affect the anti-lock braking system. I want to sell the car but do not know what to tell potential buyers. It seems like a problem that will remain unknown until something actually breaks.
Any suggestions would be much apprecaited!