Hi everybody. I'm looking for some help and advice. I have a 99 A4 2.8 quattro with an APR engine. The engine is misfiring on one bank. I've changed the MAF sensor, reset the throttle body (after a good clean) air temp sensor, coils, plugs, leads, and even the rubber piping on the pneumatic throttle system. All these have improved the misfire, and it's considerably better to drive, but it's still a little hesitant. I plugged in my V-checker, and heres the results:- 17800,p1392 bank 2 cam position sensor 2-G163 open circuit / short 17755,p1347 cam position sensor 2 G163 engine speed sensor - G28 incorrect allocation My questions are, are these one and the same sensor (although I'm again guessing that there'll be one for each bank), is this easy to do myself (I'm reasonably competent with a spanner) are these parts reasonably priced, and should I use re-seller or genuine Audi. There's a lot there and thanks in advance for any help and advice.