OBD II code help

[BimmerRacer007]

ok guys, so i received the error code P0170 which is fuel trim bank 1 fault. is this for pre-cat O2 sensors? MAF sensor? anyone know?

oh yeah, it's for an s52 in my z3 as well. (i know it's not an e36 in the traditional sense, but it's the same powertrain. im trying to get this fixed to pass emissions. lol)

thanks!

Dan

[Pirate_copy]

Hey buddy, maybe better asking in the M3 forum for this one as it is an 'M' Engine

Is there more to the error as it should say whether it is running lean or rich. From what i have read, it seems like a MAS error but the M3 guys will know more :)

I found this though

The code is for a system that cannot add enough fuel to maintain balanced air/fuel control. This can be caused by

- Vacuum leaks
- POSSIBLE MAF failure
- Restricted fuel filter
- Failing Fuel pump
- Thermostat or ECT sensor
- Failing oxygen sensor.
- Exhaust leak before the oxygen sensor

[BimmerRacer007]

thanks, yeah it's posted in the m3 section as well. im just trying to get the widest range of info. yeah, i found one vacuum leak, and i'll be searching for more when the weather lets up. from what i can tell bank 1 means that it affects cylinders 1-3 only (which is why im thinking o2 sensor and not a complete vacuum or MAF failure). i just don't wanna chase the problem with hundreds of dollars before it's fixed.