Code 171

[Sk8erprelude]

Hey guys,
I am writing on behalf of a friend with a 2001 Audi A4 with Quattro drive(manual tranny).
He has a code 171 (lean) and is wandering if there is a way to determine if it is the O2 sensor, MAF sensor or there is a way to track down the problem. We both work at a dealership (Saturn/Saab).

And what type of tranny fluid he can use (hard to shift into 2nd gear) and if it is a open or closed system for the Quattro and tranny. Basically if he changes the tranny fluid will it drain the Quattro fluid also or does he need to drain each system (tranny/Quattro ) seperately.
I hope i did not confuse you guys with that one.
Thanx for you help again.

[hdnorm2]

Originally Posted by Sk8erprelude

Hey guys,
I am writing on behalf of a friend with a 2001 Audi A4 with Quattro drive(manual tranny).
He has a code 171 (lean) and is wandering if there is a way to determine if it is the O2 sensor, MAF sensor or there is a way to track down the problem. We both work at a dealership (Saturn/Saab).

And what type of tranny fluid he can use (hard to shift into 2nd gear) and if it is a open or closed system for the Quattro and tranny. Basically if he changes the tranny fluid will it drain the Quattro fluid also or does he need to drain each system (tranny/Quattro ) seperately.
I hope i did not confuse you guys with that one.
Thanx for you help again.

there are several things to check..first check all vacuum hoses escpecially the L-shaped one behind the throttle body,then make sure the screen in the air intake box is clear..if all that is ok then the MAF is probably faulty...the small vacuum hoe in the front of the manifold is usually the culptrit as a faulty turbo by-pass valve also could be.as for the trans use 90w-100 anything to heavy will cause hard shifting and it will drain the entire unit....hope this helps