I just went to autozone and they scanned my computer for my CEL code and P0420 came up. What to check/replace? Its an 02 Audi a4 1.8t 5speed.

 

Thats the catalyst system. I'd have the cat checked out. Mine went bad about a month and a half ago.

 

Thanks. I just bought the car this week but the guy I bought it from got it as a certified used car with a warranty. Does that warranty transfer to me also? Its up in December he says. Just wondering if i'm gonna have to pay much out of pocket for this. Are they just gonna clear the code and see if it comes back or will they actually fix it?

 

You can try clearing the code to see if it was just a glitch. However if it comes back then you know you got problems. I would check out the o2 sensors, I'm not positive but think your car has two (one before and after).As for the warrantee, I would check with the Audi dealer. When my cat went my car was still covered, the cost of the parts from the dealer if it wasn't was about $1100 plus labor...luckily I didn't have to pay anything. hope you don't either.

 

I checked with the dealer yesterday. I have to pay $150 and send all my info to audi and it gets transferred into my name. $1100 for a cat converter?? I can see already this doesn't look likea car i'll be keeping for too long [&:]

 

i have the same car now with a testpipe instead of the cat so i still have my old cat perfect condition. pm me if your interested i can get it to you for a good price then you could jsut have a shop install it instead of gettin shafted by the dealership.

 

Should I try and clear the code out with a scanner and see if it comes back? I had to send all my info and a $150 paymentto Audi to transfer the CPO warranty into my name so its gonna take some time to get that all done.

 

You could try and clear it, but it's starting to sound pretty serious. If it is a bad cat, than it will just come back again.What other changes in the car are you expirencing? How's your MPG (if your2nd o2 sensor went bad it would run really rich and burn the cat)? Stuff like that...

 

There are no changes to the car in how it runs or drives. I only had the car a week now so I don't know my mpg. Im gonna fill it up tonight for the first time. It isn't sucking through gas though. I do not think its running rich.

If I clear the code with a scanner, does it clear it out of the computer or only shut the CEL off?

 

just buy the warranty and get it replaced if you want to go that route, seems like its the best option at this point. At least youll be covered until december of 08