Quote:
Originally Posted by mike_s
I wanted to follow up for anyone else that may be unaware of numerous reports of pre-cat failures on Nissan models with the QR25DE engine. While I'm not certain that this is the reason for my P0420 code, I am sufficeintly concerned about this being a potential problem and have ordered an new header with out the cat. My Sentra SE-R has a second cat down stream and from everything I've read, removal of the pre-cat will not be a problem for emmission testing.
.
|
Removal of that cat. will definately be a problem for emissions testing. You will have a constant check engine light with a P0420 code due to the missing cat.
The rear oxygen sensor is mounted behind that converter. The second cat you see down stream is not monitored by the cars computer.