Hi,

I've a 2001 A4 1.8T. Two weeks ago I got the following service/repairs done:

- 80K mile serive
- timing belt and water pump
- front cv boots, tie rod and alignment
- back brakes and rotors
- throttle body replacement to take care of surging of engine when idling

After the service/repairs, my check engine light came on. I took the car to the repair guys and he said it's P0171 bank1 system running too lean. He reset the light and asked me to drive for a bit more. This week the light came back up with same code. The repair guy thinks it's the O2 sensor or catalytic converter.

I was wondering if the service/repairs I got done had anything to do with this check engine light. There was no check engine light before these repairs.

Thanks,

 

got the same thing on my 01 1.8t its you o2 sensor

 

mine was a maf. you should try it out too

 

Check VAC lines first, much cheaper fix, thats what mine was. The hose running from the intake to the diverter valve, the leak was real loud so i spotted it right away.

 

thanks guys...

looks like it's some air-meter as per the mechanic... does it take about $300 for it? can I try to fix it myself?

 

Well Air Meter isnt very specific but your mechanic is probably talking about the MAF and it isnt that hard to replace.

 

borrowed OBD2 scanner from a friend and hooked it up... looks like P0171 is gone and now it shows P0102 (Mass or Volume Air Flow Circ Low Input)..

 

Well its likely p0171 will come back (that code only occurs after a longer term) becuase the mechanic probably cleared the codes to see what comes back. Its either vaccum lines or MAF.