Hi guys, this is my first post and won't be my last due to having my work cut out for me with an Audi A3 8L I purchased with the intention of repairing. Apologies if there is already a thread for this, or if my question is really dumb! Okay so my revs have been hunting on starting the car, and when bringing the clutch to bite to pull away the revs drop all the way down and nearly stalls the car (I have to dip the clutch to keep the engine running). I'm guessed it's either the throttle body or o2 sensor, but before doing anything I ran a scan on VCDS which threw up the following code: 00525 - Oxygen (Lambda) Sensor (G39): Signal too Low Therefore I'm guessing this is the best place to start. My question then, is how do I know which sensor needs to be replaced? The one before or after the cat? Also, does this sound like the possible solution to the problem I'm getting? Seems strange that the lambda would cause this issue. Thanks guys!!!