P0420

Discussion in 'Modifications & DIY how-to' started by Dheim96, Jan 8, 2012.

  1. Dheim96

    Dheim96 Member

    Im driving back from MD with my car and I get off the my exit in GA. As soon as I get off the check engine light comes on and the cruise control light is flashing. I went to autozone and had them pull the code. It's a P0420. Anyone ever run across this? Could be a bad O2 sensor, ignition system or A/F ratio is what they said.
     
  2. integroid

    integroid Supporting Member

    Do you have a catless downpipe?
     
  3. Dheim96

    Dheim96 Member

    Stock downpipe
     
  4. b reel

    b reel Active Member

    question is do you have an AP or open source tune? The code can be turned off
     
  5. integroid

    integroid Supporting Member

    yeah but why is it coming up to begin with when he has a stock downpipe. Clear the code and see if it comes back. It might have been a fluke.
     
  6. wagunz_pwn

    wagunz_pwn Active Member

    Probably a bad O2 sensor.

    You could also try cleaning your maf.
     
  7. Dheim96

    Dheim96 Member

    I don't have either.
     
  8. Matt

    Matt Think before you post Staff Member Supporting Member

    catalyst inefficiency is typically a bad o2 sensor.
     
  9. GTscoob

    GTscoob Black is Beautiful

    Most definitely if the rest of the car is stock.
     
  10. Dheim96

    Dheim96 Member

    So, the check engine light went off yesterday. I didn't do anything. works for me.
     
  11. integroid

    integroid Supporting Member

    It will go off after a few hours of driving. I would get it cleared and then see if it comes back on.
     
  12. Dheim96

    Dheim96 Member

    The weird thing is that the light was on for about 4 days and then just went off yesterday.
     
  13. Jake

    Jake Active Member

    it does that. doesnt mean the O2 magically fixed itself. its still in there.
     
  14. Dheim96

    Dheim96 Member

    I'll have autozone clear the code and then see what happens.
     
  15. CelticPride

    CelticPride Banned

    o2 doesn't fix itself....it just didn't pop that code again in so many drive cycles.

    If you as much as look at the o2, it'll die on you :|
     

Share This Page