Hissing noise behind the seats
 

Looking for some input about a possible vacuum leak that I hear only with engine running coming from underneath the rear compartments. I can't tell if its normal (maybe fuel pump) or if it is a vacuum line. Once in a while when I shut the trunk, it doesn't pull it down all the way and make that click noise. Can't tell if its related. Took the car to the dealer and they said they could not hear anything and of course the trunk worked perfectly...

if you close the trunk and it doesnt pull down, you can hear a vacuum leak coming from the trunk lock. that is a break in the plastic in the trunk lock mechanism.
the dealer can replace the whole unit or it could be fixed with some epoxy if you take it apart.
If it is somewhere else in the vacuum system you would have to find it first.

:D

Just wondering if anyone else can hear a hissing noise coming from behind the seats with the car in park and idleing with the windows up?

They said it was my fuel pump, then a few months later my central locking
stopped working, never did find out, but sure it's gonna cost whether it's the fuel pump or the sbc pump that's why I changed to a SL63 and no probs in
18 months.:y