O2 sensors didn't read during smog

[Jay B7]

05 s4 Avant, Smogged my ride recently and everything was fine with the exception that the o2 sensors had no value yet. Had some new keys programmed by the dealer. My only answer would be that the ECU had a reset when programming the transponders. Drove a total of maybe 70 miles after the programming until I smogged the car. Would this be a logical thought? If so, how many miles should I give it before trying to smog it again?

TIA

[Jay B7]

bump, catalyst not ready was the exact words. I read that it could be a O2 Delete in ecu? any ideas?

[jmcS4]

sounds like your S4 is tuned. or both your rear 02's are completely dead which means you would be getting shitty mpg's and poor performance

[RPMtech147]

The cat monitor has not gone 'ready'. Just needs to be driven more. It can take while the way audi has their monitors setup. Also, if the cats are OE with a ton of miles the monitor takes longer to go ready because the chemical reaction is not as efficient in the TWC as when it was new.

[Jay B7]

cool thanks. gonna take it in a little bit to re-smog it

[pwest15]

Yeah I had this same issue when I last had to get emissions done. Just have to drive it a ton. I'd disconnected the battery a few days before going to get emissions done and the a few of the systems were not readying "ready" so they told me to drive it more. I kept driving it and went back to check once a week for a whole month until finally the systems read "ready" and they passed me. From the time I'd disconnected the battery to the time I finally got it passed, it had maybe about 50-75 drive cycles with about 700 miles put on the car.