P0420

**Justin23454** · 01-07-2009, 02:29 PM

ok I replaced my o2's and now I get the P0420 code (which I think its fine since I have gutted cats). Am I assuming correctly? Just need to get my comp tuned now right?

**2001NBMZ28** · 01-07-2009, 02:54 PM

P0420 and P0430 are cat inefficiency codes from the rear 02 sensors, if you've gutted the cats have them turned off. Ask your tuner about other cat related tuning too, like COT.

**Justin23454** · 01-07-2009, 04:05 PM

ya I have not had anything done to my car after my mods. I know I need to though gonna do it really soon. Probly send to frost or something.

**Frost** · 01-08-2009, 05:19 AM

or drive over here and put it on the rollers; whichever you'd prefer... UPS (and FedEx most likely) is overnight between us shipping via ground, so that's nice.