well i've been getting a p0171 code lately, on and off. I believe it's to do with the o2 sensor (how easily/often do these fail?)... but the definition lists a number of things, but I'm not sure where to start and kind of hesitant to start seeing as it's freezing outside and i haven't got a garage to work in.

Anyway, I've gotten an egg smell a few times, which usually indicates the catalytic converter.. could it be possible the problems related.. it makes sense to me. Any advice from anyone i will be greatly appreciated.

I've got an 01 a4 w/ 62k miles (which I believe means my cat is still under warranty.. should I just go to audi and have them look at it? think they'd charge me if it wasn't my cat?). I thought the code came up because I took apart my airbox, and putting it back together i think i lost something, because my secondary air pump feed doesn't want to reattach with the rubber part in there.. so it may be a little loose, would that cause the code?

Thanks!

 

i think this problem would be universal, not just b5 related. Anyone have any ideas? Thanks