Hi guys, I have a check engine on my car, I get a P0420 code "Catalyst System Efficiency Below Threshold (bank 1)" when I scan my car. I have no symptoms and I installed my MPX exhaust system last week, I still have my cat below the car. How can I solve this problem? Put a spacer on my catalytic sensor?

Thanks.

 

Weird. I just got the same code this morning for the same thing.

 

See if the cat is still under warranty

 

No, I get an MPX cat! And my check engine is code on my dashboard, I don't understand at all...

 

It does not matter if you still have a cat. You can still throw this code with anything aftermarket. Either remove the piece or get a tune that removes the code.

 

I'll get a tune next month so it's don't bother me at all!

 

Sweet, just make sure to tell your tuner what downpipe you have and that you want the cat codes turned off in the tune. NBD.

Have fun.

 

Thanks for your input dude!