I love my Audi A6 4.2L but there is a tapping noise that is beginning to drive my nuts. Its really low but I can hear it. I've stayed on top of maintenance, I even switched to a fully synthetic oil and its still there. Now have been on the forums searching for answers and I've heard everything from "it could be valve tapping, oil pump about to go out, and even hydraulic lifter problems" If anyone one has any ideas or suggestions on how I can decipher the difference. PLEASE HELP cause I sold my other vehicle and this is my only means of transpo. Thanks

 

It is going to be hard to pinpoint the exact problem without being there in person and hearing it. I would say your best bet is to take it to a garage and have them diagnose the problem. If you don't want to do that you can try to get your hands on an automotive stethoscope and listen to each problem area to determine if that's the cause of the tapping.