Thread: To keep cat converter or not...01 prix

I have a 2001 Grand Prix 3800 non supercharged with about 115,000 miles. It has a po420 code and is said to have a bad cat/ actually a shop told me it was the wrong cat on the car.. Iv had the car for about 8 months. It sometimes has rotten egg smell and the codes is affecting gas mileage. I'm looking to drive the car about 65 miles a day highway driving, a few times a week, to school, and of course normal city driving. So I have to get it taken care of.

The car has already had the typical trans long shaft code problem, which I installed a shift kit and it seemed to straighten that out for now. I know that its considered a temporary fix.


I like the sound of the stock exhaust and it seems to run fine, of course I'm looking to put as less money into the car as possible seeing how the issues Iv named and I'm a student. I also heard about a idea with installing a glass pack muffler where the converter is, to keep the sound stock. But maybe I'm mistaken.

Anyway I am aware of the o2 simulators or having to write out the code form the cpu. There is no visual emission test, just a code scan during inspection.


I am not totally against getting another cat put in, if it is the more logical thing to do. I have read around and there are many diff opinions. that is why I tried to mention my application and driving situation.

Originally Posted by dsmuts

I'd run a catless dp on it and not have to worry about it anymore. Your's being an 01 may have the cat diagnostic test that dump fuel into the motor until the rear o2 sees the rear cat is working then stops it.

So that's a possible test that emission may do? So wouldn't a catless down-pipe be successible to that test...Maybe that's what your saying

Originally Posted by ctracer

just get a cheap converter. seriously, that way you wont have to deal with anything else.

That may be what I'll do. Considering no matter what, Ill have to trick the computer...besides getting a oem cat.