P0420 code

[Beats]

Had P0420 code pop up while driving. Says it's a catalytic problem. Cleared the code a few minutes after I scanned. I'm reading it might be a problem with the cat or an O2 sensor. I just got my car running after a month long wait. I ended up replacing the PCV diaphragm. Anyways I cleared the codes and the car has been running for a 10-15 minutes and no CIL.

Any suggestions people? My car has 117k miles so I'm not covered under the 80k mile warranty for the cat.

[bluetori]

If the cat is gone replace it with a HFC or a test pipe. Alternatively you could test it with a voltmeter to see if the o2 sensor still works, it shouldn't be done yet but you never know.

[kt883]

I have the same code. Your cat is covered under federal emissions warranty for much longer than 80k so give that a try at dealer. If you have any problems with your car they wil try toblame that as the cause.

I believe mine was caused by stuck injector but because I have bad turbo WG they blame that and wont fix (even though that is covered but past km for that).

Suggest reading the DIY on cat removal and examine the substrate material.