pouliotk2441
01-03-2021, 12:52 PM
Hey guys, quick question. My father has a c7 A6 3.0t. No mods besides pulley and stage 2 giac tune. After the tune he was getting an “O2 B1S2, slow response rich to lean” code plus “bank 2 efficiency below threshold” code. All 4 O2’s were just changed with OEM Audi sensors and now he’s getting “undocumented codes, 49E500H/484275 and 33D900H/3397888.” From what I’ve read, GIAC is based out of Cali and they’re trying to be legal so their tunes don’t shut the rear 02’s off. Anyone deal with this before? Are the cats shot? The car still runs good/rips but if the lights gonna stay on due to the tune it would be good to know before buying new cats. Spacers have been used without help as well. The light isn’t a big issue to us, but being in Mass it, it won’t pass emissions. Any advice and thank you.