got a 2001 a4 1.8t. just bought it a month ago and the cel went on. i got code p0171 "bank 1 system too lean." brought it in to get diagnostics done there was multiple misfire codes (no surprise) and p1176 "o2 correction behind catalyst, b1 controlled limit reached" and p1426 "evap canister purge valve, open circuit, sporatic." I am trying to decide what this all means. i haven't done anything yet cause i dont have the money to start throwing parts at it. i am thinking it migh be the o2 sensor before the cat. I checked the evap purge valve and it read 28 ohms which i believe is within tolerance. any help would be awesome! if you have any questions on arctic cat sleds, would be happy to help in return!!!

 

you either have a vacuum leak or that 02 sensor needs to be cleaned/replaced.

 

already checked all the hoses i could find. everything seems good. would it be worth to smoke test before i get a sensor? i found a quality bosch sensor on ebay for bout 50 bucks. cant argue with that price

 

I put $5 on a bad maf. Usually when the 02 sensor can't correct a/f correctly you'll get an 02 specific code. Usually when the maf is bad you get a lean code. Usually when you have a vac leak your engine idles like crap. You'd have to have a giant gaping vac leak to get a lean code, and your engine would probably stall a lot.


Those fault codes could be old and irrelevant. Clear them and see what comes back.

 

got the same code p0171 going on in my 01 1.8t im 85% sure its my o2 but let me know what you find

 

already cleared many times and p0171 and misfires come back. ill go into more detail bout whats happening. i clear the codes and restart the car warm. idles just fine. i rev the engine a little and almost sounds like its backfiring (misfires?). take it on the street and it runs like crap in first and second gears. get into third and it runs alright. stop at stop light and it gots lots of power and drives fine for bout ten miles. after that i notice quite a bit of lost power. it almost seems like it isnt boosting because it revs fine, it just doesnt go anywhere. after a day or so the cel comes on again with same codes. i could clear them and the same exact thing would happen all over again.

 

My money is still on the maf. It'll put you into limp mode which is probably what you are describing with the lack of power.

 

well the lack of power is by no means limp mode. the car stills moves but after clearing the codes for the first few hundred feet it is definaely limp mode. where can i get an maf cheap?

 

i have the same code im pretty sure, cylinder 4 too lean ...


??

 

Limp mode just means scaled back timing and boost along with a more conservative fuel map. ECU see's somthing wrong with A/F correction/input and freaks out and plays it safe. Car is still plenty driveable though. A maf is something I wouldn't get used, so try www.ecstuning.com. I think they usually have the best deal on them. Not cheap though.