robbellbottom

Here's my story:

I have a 2001 Allroad. The check engine light has come on with the code P0421. I know from research on here and what my scanner says is that that is a cat problem. I continued reset it a couple of times and it would come back on after 150 miles or so. I have had the ECU reflashed and that didn't fix it. I gave up on resetting the code and figured I would just deal with it until I have the time and $$ to fix it. Well lately it has been going out on it's own. It will stay out for no specific time or mileage and then will come back on.

Is this a normal MO for a computer to clear it's code on it's own after a while?

It was mentioned in other posts here about a burning smell. I get that when the engine is cold but after it warms up from driving for a little while that smell is gone. I had read something about gaskets that expand when they warm and then they seal better. Could this be realated?

Dana @ Ross-Tech

Post your scan data.

The faults do not erase or go away, but they will go to intermittent after passing a few self tests. The check engine light would turn off until it fails the test again.