I'm back. The ambient temperature was 80 degrees with low humidity. I had 40-41 degrees out of the center vent with recirc on, full blast. With the low side valve closed at the manifold my readings were 35 low, 275 high. Thanks -

Sorry for the late reply. I will perform this test in the next couple of days and report back. Thanks again.

The system is virtually untouched from when I repaired it a year ago, hasn't been recharged. Thanks -

The noise started when I had it charged. I ruled out the blower motor because it also does it when the blower motor is disconnected. Changing the temperature slider doesn't change anything, noise-wise. There is no noise when I change it to heat.

Thanks -

Hello, new here. I'm having a problem, sort of, with the a/c on a '83 El Camino. I bought this car a year ago and immediately replaced the compressor, the accumulator, o-rings and orefice tube. I had it professionally flushed, vacuumed, oiled and charged and it's been working great for the last year...