i've always wondered about this but never thought to ask:

on my car, the rear deck "astro ventilation" vents right behind the back window are plugged from underneath.  it looks like the plug is riveted to the vent and cannot be removed.
i've seen this many times on other cars but  i've also seen them open on others.  can someone tell me why my vents are closed off?
thanks!

You have air conditioning, don't you?  All air cars have those plugged. Astro ventilation only is for non air cars.

wow! thanks!  I never knew that.
that explains a lot.

Yeppers, A/C cars had the vents blocked off, as they weren't needed. The plug is epoxied/glassed onto the rear deck. If someone puts too long of a screw in the vent grill back there, it will poke a hole in 'glass, and presto...water leak...just like the real thing!

Funny thing about those vents...even the convertible cars had them...but they didn't do anything...they are behind the passenger compartment! If you look down thru them, you'll see pavement!

They were originally functional on "The Toy" for one or more of the P.O.s but over time they were stuck open.  LOTS of water found its way into the luggage area...!!!  I just took some long screws and closed them.  Maybe some day I'll try to get them functional again but for the meantime I like having a dry luggage compartment...!!!