Thread: 2005 Grand Prix Issues

Ok, so I have been having a few issues with my 2005 Grand Prix GT 3800 V6.

1. Transmission will intermittently shift hard. It usually starts when I get off the interstate and stop at a stop light and then go again. Talked to a transmission guy and have him see if there are any codes. He didn't even have to run the scanner and he was fairly certain what the problem was. He ran the scanner and sure enough it had a transmission solenoid code. So I think I have that problem narrowed down but would appreciate any advice if it could be anything else.

2. I have a catalytic emissions code. I have the codes cleared and it seems to only pop the code when the transmission starts acting up.

3. Sometimes I have a problem getting it started after sitting for a bit. Example, I will come home on my lunch break and let it sit for about 45 minutes and I go try and start it and it won't. Sometimes it takes 3 or 4 times before it starts and if that doesn't work, I have to give it some gas and it starts right up.

4. My traction control off light comes on intermittently, and when the light is on it shifts hard, I will be driving 60 mph and it is still reading 2500 rpms. No ABS light on though.

5. I have it set so my doors lock when put in drive and unlock when put in park. I noticed this around the same time that the traction control off light came on. And just tonight they didn't lock when I put in drive but after a few minutes of driving the randomly locked. I parked the car and after a few minutes I put it back in drive and they locked.

Any help would be greatly appreciated. I don't want to start throwing parts at it.
Thank you!!

I work at a mechanic/body shop and according to the mechanic he has cleaned the throttle body.

The codes I have are

P1811
P0420

Getting the solenoid replaced on Monday. According to the tranny guy this should take care of my problem without having to have it rebuilt. Here's to hoping that is the case!

+1 to cleaning the TB yourself. You can pull it off easy and do a good job of it. I had that exact issue, and since then I just clean the TB once or twice a year.

Like it was said, consider a pan drop and a fluid change. A shift kit will also help save your 4th gear hub.

I have had the traction control and door look issue before, right after I bought my car. It was a bad wheel speed sensor and harness. I was still under factory warranty, so they put in 2 new wheel barrings (the sensor can't be separated, and they said another was almost shot), and a new harness for one of them.