Head
Are you going to fumble around with customer's car?
You may end up damaging the engine and cost you more money than profit.
Please send it to a proper VAG specialized shop.
https://erwin.audiusa.com/erwin/showHome.do
I suggest you purchase a one day subscription to erWIN (As I recall, it is USD$35 or so, but YMMMV.) And download the relevant repair manuals, wiring diagrams, and TSB's (if required) for the vehicle in question. (Most documents are in PDF.) Note, ERWIN does not limit the number of downloads you make in a subscription period, so I also suggest you err towards being more inclusive in your searches.



