Chevy & GMC Vans

Posted: **Wed Nov 28, 2012 9:45 am**

Well, I ran it again and no more code P420. I guess it too needed a bunch of time (cycles) to clear itself. Over a 1000 miles!

I'll consider this case closed, thanks for your help and advice.

And Merry Christmas!

Posted: **Fri Nov 30, 2012 4:20 am**

Congrats! Hopefully it stays that way!

Posted: **Thu Nov 28, 2013 11:02 am**

Went up steep hill in So Cal Tahacapi mts and floored my 2003 AWD , got Service Eng Light, P302'. Cyl 2 miss fire.

Wonder if plug fouled, or?

Chevy & GMC Vans

OBDII says P420, O2 Sensor

Re: OBDII says P420, O2 Sensor

Re: OBDII says P420, O2 Sensor

Re: OBDII says P420, O2 Sensor