Alright so I got a P0421 when my car was scanned.
Definition: Catalyst efficiency low - bank 1.
Can someone help me troubleshoot my car?
1) I got my upstream O2 sensor replaced already and that didn't solve the problem.
2) My catalytic converter can't be the problem because I don't really notice any of the symptoms of a bad cat. Right?
3) My engine isn't misfiring, so it can't be that, right?
4) I don't think I have a large vacuum leak, how can I tell?
5) I don't know if engine oil is leaking into the exhaust-valve guide seals, piston rings. How can I tell?
So I'm hoping my problem can be solved with the replacement of the downstream O2 sensor.
Anyone have any idea what could be the problem? I don't want to be paying for more replacements if that's not what needs to be replaced (ie: how I wasted money on getting the O2 sensor replaced when it didn't need to be).
Definition: Catalyst efficiency low - bank 1.
Can someone help me troubleshoot my car?
1) I got my upstream O2 sensor replaced already and that didn't solve the problem.
2) My catalytic converter can't be the problem because I don't really notice any of the symptoms of a bad cat. Right?
3) My engine isn't misfiring, so it can't be that, right?
4) I don't think I have a large vacuum leak, how can I tell?
5) I don't know if engine oil is leaking into the exhaust-valve guide seals, piston rings. How can I tell?
So I'm hoping my problem can be solved with the replacement of the downstream O2 sensor.
Anyone have any idea what could be the problem? I don't want to be paying for more replacements if that's not what needs to be replaced (ie: how I wasted money on getting the O2 sensor replaced when it didn't need to be).