Hi,

I've had a recurring P0420 code for a bad catalytic converter. The cat seems like the obvious solution. The ECU has the latest software. Is there any chance the bad reading at the cat is actually just a result of a bad MAF sensor upstream?

Thanks,
Matt

 

No, usually associated with intake air leaks or injector problems. What mods have you got?

 

No mods on the intake, all stock except for K+N air filter.

 

Performance OK? Any surging/hunting, throttle hanging (if a MT), idle stable and around 700 when warm?

 

Yes to all.

The car is a little slower than it used to but that's understandable for a car with 87K miles. I was planning to replace the MAF sensor just for the hell of it, and I was hoping it might take care of the P0420 problem.

 

I would get to a dealer on this. Your Fed. emissions warranty may cover it AND there is a TSB 00070 (NTB 00-070b) for a P0420 DTC that may apply to your car if it hasn't already been accomplished. FIRST.......get that K&N air filter replaced with any non-oiled one. FYI, the ECM and MAF/sensor element/ASSEMBLY have to be "matched". This is not an option, contrary to some.

 

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