PasPar2

Steady CEL came on during the commute to work this AM. Durameteric shows its P0420. Search here is not conclusive - either O2 or the cat itself.

How do I test to see which it is? Can it all be done using the durametric or will I need to remove/unplug any O2 sensor?

what side of the car is bank 1?

02 996 c2 with 88k miles on body (and exhaust system) and ~7k miles on new engine so maf has 7k miles on it and so does the air filter and throttle body (possible I need to clean any of those?!)

Thanks

Macster

My info is if the P0420 (or P0430) code not accompanied by any aging O2 sensor codes the problem is with the converter(s).

Furthermore, my inf is if there are O2 sensor aging code(s) the recommended procedure is to replace the O2 sensor(s) and clear the codes and drive the car to see if the P0420/P0430 codes reappear.

You can check the throttle body to see if it requires cleaning. It may be a bit gunky with oil from the AOS. This does not mean the AOS is bad just that due to the proximity of the AOS hose to the intake manifold oil vapors over time can foul the throttle body. Won't help the P0420 code though. But you'll feel better eliminating the TB is my guess.

My 02 Boxster has been emitting a P0430 code now for over 2 years, off and on, sometimes every couple of weeks and in warmer weather sometimes not for several months. I'm not replacing the converter(s) until I have to to get the car to pass smog. So far it has passed, but the margin is shrinking. And last time just a while after the smog test the CEL came on. Good old P0430.

Sincerely,

Macster.

PasPar2

Thanks Macster. I'll be honest, I called code brown when it came on (images of an IMS failure in my head) but didnt feel any difference in idle or see any smoke and everything seemed ok so I just continued to work and read up that a steady light is ok to drive on.

PasPar2

is there a way to test the o2 sensors? i have a durametric if that helps....

edit : idle and 3k rpm durametric screen shots - can anyone translate? the number change a lot so this may be futile...

67FJ45

PasPar2, if you pm me with your email address I can send you excel data sheets and charts, showing how to set up the Durametric and what to diagnose. I've done this with both good and bad cats.

PasPar2

thanks for the offer!!! pm sent.