1992 Civic LX

I am trying to get my daughters civic ready to take back to school this
fall and I have a couple of strange problems I can't run down. Car has
183,000 miles and I just did a very complete service job on it but the
problems still exist.

The first problem I thought was a hoax when my daughter would come home
and tell me her car hissed at her but after driving it myself for a few
days it finally hissed for me today, sounds like a pressure release
possibly from the fuel tank. Any ideas?

The second problem is that the AC clutch stops engaging when ever it
decides to. I haven't been able to narrow it down any more, it may work
fine for a day or two and then for instance today it stopped cooling
about 5 minutes after startup and didn't work for the entire trip home
( 20 minutes) when I got home I hooked up the pressure gauges and
everything seemed OK. I let the car set for 30 minutes and when I
started it again the clutch kicked in and it cooled for a while and
stopped again. I think I'm in over my head here guy's!

 

What kind of refigerant is in your car and what were the pressure readings
(low and hi) at idle and at about 2,500 to 3,000 rpm. Has the AC been
working and all of a sudden it quit or what? More details please.