QuestionI am getting the p0422 error. I can make it go away and it doesnt come back for a while. Does anyone know which Oxygen sensor it might be? Also when my catalytic converter went I paniced and went to a mechanic who replaced it with aftermarket. I guess its too late to go to a delership and will this be a problem in a long run?
AnswerP0422 means your manifold catalyst efficiency is low. On your car, this catalytic converter is part of the exhaust manifold.
First, I'd recommend calling your local dealer and seeing if there are any open service campaigns on your car. Campaign V04 involves the inspection of the exhaust manifold and, if it's cracked, replacing the exhaust manifold. If the campaign is still open on your vehicle and the manifold is cracked, you should get a new manifold and converter.
Additionally, if you have less than 80,000 miles on the car, the converter should be covered under warranty. If you've got more than 80,000 miles and the recall is no longer open, presuming the check engine lamp and P0422 were the original reason for servicing, you should probably return to the original mechanic to request the vehicle be correctly repaired. I'm figuring the mechanic either replaced the rear catalytic coverter (the one underneath the car) or replaced the manifold catalytic converter with one that isn't good enough. In the former case, you should receive financial consideration because the mechanic replaced the incorrect converter, and in the latter, you should be entitled to a free repair because the installed part was defective.
If the mechanic replaced the rear converter and not the manifold converter, you shouldn't have any issues with denial of warranty coverage.
Additionally, I believe it is not legal to install an aftermarket converter while the car is still within the warranty period. If you're still under 80,000 miles, you may want to look into that as well.
