After starting up my 850 turbo, all seems fine with the AC, but after 30-45 minutes driving, it starts putting out hot air. Eventually, it'll cool off again, and if I turn the car off for a couple hours, it will work fine when I restart.

Last week I bought a combo r-134 and pressure gauge. I got 45 psi, at the high end of normal with the engine warm and running, AC cranked up all the way.

Later that week, I was pulling into my driveway with the AC blowing hot. Checked the pressure and it was at 100+. Scary.

Today, I started the car and hooked up the pressure gauge. Got 45 psi. Let it run for a little while and pressure started rising till it was at 55 psi, in the middle of the "alert" range. Turned on the recirculate button on the climate control, and the pressure went back down to 40-45 range. Lather, rinse, repeat with same results.If recirc is on, pressure in the 40-45 range, turn recirc off and watch it climb to 55 in about 15 seconds, then recirc on and it falls again.

All the while it's putting out cold air. I can never seem to duplicate a problem when I have tools and time to do something about it,.

Drove around for 40 minutes and continued to get cool air with the recirc set on.

The compressor will engage and disengage when I swith the AC from "off" to "aut" but doesn't seem to cycle a whole lot otherwise.

Both pipes that head into the firewall are cold. Very cold.

Thoughts, ideas, suggestions?

Bueller?

Bueller?

If you need more information, I'll try to answer to the best of my ability.

Todd
affirmed(at)mindspring.com