I have a 2006 2.0 TDI A3 which I bought off a friend, when buying it there was a fault code - engine management light has been on for a while and he told me it had been checked and it was the 'MAF sensor' which he was told looks like a butterfly valve but due to position in engine bay will cost a lot in labour costs. I'm not sure that sounds right as the MAF sensor seems to be at the top of the engine bay attached to the air box? Maybe he was thinking of something else?
Basically I thought it maybe best to check the fault code again using on the readers off ebay?
Audi A2 A3 A4 A6 A8 Fault Code Reader Scanner diagnostic scan tool | eBay
These seem a bit too cheap to be good? Anyone had any experience with these?