I hear a hissing noise when I enter the car; it comes from the rear
passenger side. Lasts a couple of seconds, then goes away.
(I had an accident couple of years back; the rear passenger side quarter
panel was hit pretty bad and was rebuilt. Looks good as new now, but on
close inspection the door lock on the rear passenger door seats slightly
lower into the door than do all the other door locks when they're locked,
not quite as flush with the door as the others.)
Am I just hearing the fuel pump when I get in? Or does Audi use compressed
air to control the door locking mechanisms? I'm wondering if I've got an
air leak that will eventually cost me a bundle when/if it no longer
locks/unlocks my doors.
Any ideas? Or am I just an auto-hypochondriac?