View Full Version : Grand Prix is being a bit of trouble

02-16-2011, 07:09 PM
So, it has 261k on it and so things are going to happen. Well, it started acting up with the transmission searching and lurching a bit. Not bad, so I thought it was the typical GP tranmission issue.

Watched my fuel mileage drop and power drop, so I took the O2 sensor out of it and sure enough it ran better and it's setting a code of P0404 which means the EGR valve can't return to it's requested location. So, all in all that means the cat is plugging up.

Luckily I found a DownPipe without a cat and will be installing it tomorrow hopefully. I have all the tools, but a jack or stands to put it up on. This also requires that the rear 02 be deleted from the PCM, but I don't have any tuning information to be able to do that.

At this point hoping to be able to get it home and change it there as long as the cat doesn't plug completely on the way.

Not complaining, just venting a bit. Carry on.

02-16-2011, 09:47 PM
Best of luck man...at least it's been warming up

02-17-2011, 10:43 PM
What happens when 2 SC'ers work on a Grand Prix?

The Grand Prix acts like a SC and was extremely stubborn.

Have a safe event free trip home tomorrow.

02-17-2011, 10:54 PM
Thank you thank you thank you. Very nice having the moral support that did end up being physical labor. :D

It does sound and act a bit different. All is better, but the raspy rice sound. Was it bad when I pulled away from your place?

02-17-2011, 11:04 PM
I live in southern Illinois and have a gp and soon another sc. The site that will help you the most is http://www.grandprixforums.net/

02-18-2011, 08:59 AM
All is better, but the raspy rice sound. Was it bad when I pulled away from your place?

No, not really, but I would have thought it would be quieter.