I'm hoping someone can help. I've had my hhr for about 3 1/2 years now, and recently i have been having a problem where I will put the car into park and leave it idle for about five minutes, and when i put it back into drive, my T/C light is lit up.(This has never happened before)

Also, the transmission will be shifting very rough. Whenever you put it into Reverse or Drive, it makes a loud bang sound, and the whole car jumps forward. It is the same when it is shifting from first to second, second to third, and third to fourth. You hear a loud bang, and rather than a smooth shift, it is an extremely rough shift.

After about 10 minutes of driving, the transmission resumes to normal, and when the car is shut off and turned back on, the T/C light is no longer lit up. I took it to the dealer recently, and they could not duplicate the problem, or find any error codes. I brought it back to them while the traction light was lit up, and they scanned it for codes, but still could not find anything.

I'm hoping that someone else has had this problem and can help me!! Thanks

 

Many of us have had a similar problem after installing a different air filter. After I put my CGS intake on, if I did a hard start and spun the tires, the T/C light would come on along with the hard shifting. Then it started coming on anytime I stepped on the gas, then when I was coasting, finally it sometime comes on when I am stopped at a traffic light. Is your intake stock or was it changed?

Possible theories have included a dirty MAS (from oiled filter). I am just living with it until I have time to get around to it.

 

this happened on my saturn . the transmission mounts came off and the tranny was just hanging there and i didn't notice it till it was too late and i lost reverse gear.

 

T/C light and hard shifts is the HHR "limp mode" (sort of) It can have lots of causes..... If there's a CEL, get the codes, could be cam position sensors (there's a how to here on replacement) a disconnected MAF (from those pesky guys at the oil change places that can't figure out how to change the air filter) modified air intake (as mentioned above) Etc. etc. etc.

 

But the cool part is that in that 'hard shift' mode' the car chirps its tires when it shifts to second