I have 2003 Saturn L200 w/automatic transmission that is having trouble upshifting. The problem is as follows: When I accelerate, the car does not want to upshift. The engine will go up to 4000 RPM and then get pulled down in RPM, because the transmission won't upshift. Once I let off the throttle, the transmission automatically upshifts. The check engine light came on for a short time, but then went off. I changed the Throttle Position Sensor, but doesn't seem to have made a significant difference.


I am open to suggestions, please help.

I don't know anything about 2003, but I was have problems with my 95 tranny. My 95 has a performance mode switch, which will give the same kind of symptom your having. I also changed my transmission fluid to synthetic because of problems with up shifting in cold weather. I also found my fuses for the transmission had become tarnished which was also effecting my shift points. Before I cleaned them up, it was shifting around 3.5k, after cleaning it dropped to 1.8k. Like I said, I don't know if any of this applies to you but it might give you some ideas to explore.

I got the same problem with a 2002 LW200. Have you fixed it yet?Edited by: sw2cam

Update, the Saturn dealer found the catalatic converter needed to be replaced. The loss of power looked like transmission trouble to me.

What could cause it to go bad?Edited by: charlieott