hi everyone,i'm a .new member.i am considering buying a 1985 b2 90 quattro but the only thing is the diff lock is stuck on.is this a major problem,how can it be fixed or should i just steer clear?any help much appreciated.
Good news. I just purchased another Audi 80 Q that had a similar problem. Your Quattro control module is either bad, or servo that engages the drivetrain is stuck. To diagnose, remove all body wear around the quattro switch and test the switch for engagement and disengagement, and that all contacts are clean and seat correctly. Trace the wires from the switch back to under the rear seat (which will be removed) and under that you will find a box mounted in the center that is the quattro control module-- completely vacuum operated. Used ones can be purchased...
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