Shock Absorber Piston pushing up through Strut Upper Mounting Cover

[mboucher70 hotmail.com]

Took the car to the mechanic last week to put the snow tires on.  Driving home, I noticed a new noise from the front driver’s side.  It seemed to be suspension related...heard it most when driving over slightly bumpy areas.  Not loud, almost imperceptible, but sounds as though something is rubbing/chirping/moving that shouldn’t be.

With car parked, I pressed down on the driver’s side front fender to see if I could hear the problem.  Then I noticed that the shock absorber piston and nut would move upwards whenever I pressed down on the fender.  It certainly wasn’t like this in the past, nor is it like that on the passenger side.

The first thought would be that the piston nut needs tightening.  However, it’s a locknut, and moreover it doesn’t appear to have loosened from its usual position.  Before taking it back to the mechanic I’m going to buy the correct size Allen key so that I can hold the piston while attempting to tighten the nut.  I doubt it will tighten, but I’d be able to verify that its tight.  

The question I had...since the problem seems to coincide with the car being jacked up, is it likely that something just slipped out of position, such as a worn dampening ring or bump stop...something that would give the shock piston more room to push upwards?  

Car drives fine, even at speed...no pulling or unusual sensation in the steering....just the new noise.

Thanks

MC
Audi 100 1990 Non-Quattro