I need to install my cat for emissions testing, and I was going to flash the ECU back to the maps that I was tuned on with the cat. Will flashing the ECU reset the OBD2 readiness counters?

 

i beilive so. All cars in general are like that. You might have to drive it around for a little bit before you go in for emissions testing.

 

why flash back to stock? just put defoulers on and pass w/o cat. I just did.

 

My area does a visual cat test and OBD2 check. I'm not worried about tail pipe emissions, but you can tell the car is catless by the smell.

 

What is a defoulers?

 

Why use hardware to solve a software issue? (benderrodriguez: he's referring to the use of spark plug anti-foulers to dilute the exhaust gas enough that your rear O2 doesn't throw a code.)

Reflashing the ECU on an IX may wipe the OBD-II readiness code (fuel trims get wiped on a reflash on IX ECUs; I have no idea if anything else is reset as well, ie. if it's a full memory wipe, or just a few regions). On an VIII, however, I don't recall readiness states ever being reset with reflashes.

That all being said: if you're in a position to reflash the ECU, why not simply take control of the readiness codes and set them to whatever you want?

(This doesn't help you with the visual inspection, unfortunately. Have you considered having an exhaust shop weld the outer shielding of a cat onto a test pipe for you, as a permanent solution?)

 

I get it now. Thanks