One problem related to wiring has been reported for the 1996 Audi A6. The most recently reported issues are listed below.
"check engine" light remains on despite repeated visits to the dealer. First it was diagnosed with failed "vaccum line," but three months later the same "check engine" light came back. Corrective measures have since included the change oxygen sensors, fuel lines, and a new battery. The light is still permanently on, although no noticable drivability is affected.