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Good morning fam! I have a 2014 gmc sierra 5.3l 2wd that is having ac problems. when the compressor is commanded on when pressing the ac button it engages for for a few seconds then starts to screech really loud until you turn it off. First thing was replace the compressor which I did and I also did the complete kit including condenser only to realize its doing it again. So I noticed when i disconnected the pressure control solenoid it doesn't scream for help only until i plug it back in. Im wondering if the HVAC control module could be faulty or how could iu test the pressure solenoid with a scope to see if there is something going on with the circuits or module itself? Andy feedback would be awesome thank you in advance.
The sound you describe could be multiple things. A poorly tracking belt, slipping compressor clutch, under lubrication, pressure relief valve blowing off etc.
Have you checked it running with gauges on the system?
I have replaced the belt and nearly the entire system, including the lines, as part of a full kit installation. The only component left untouched was the evaporator, yet I am experiencing the same results. I flushed the evaporator as well and I tested the A/C compressor solenoid valve, and it checked out fine. I suspected excessive pressure buildup, so I connected the gauges. The low side read slightly high, while the high side was around 120 psi, which suggests either a blockage or a failing compressor. When the clutch engages, the compressor appears to want to lock up; however, when the clutch is disengaged, it spins freely.
you could have got a bad compressor did you replace ten and belt or is it driven off serp or seperate even tho its doing same thing the pressure on high side is deff low
I had the same thought that perhaps I got a faulty compressor. What are the odds of three faulty compressors? We’ve already replaced three new ones, and the problem persists. I’ve also examined the control valve on the compressor, and when I disconnect it, the loud screaming stops, and the clutch spins freely. I’m quite confused because I’ve never experienced this type of issue before. I’m thinking that the high pressure buildup on the low side might be causing the clutch to disintegrate. I usually don’t like to replace parts, but at this point, I’m considering that there might be a blockage inside the evaporator causing this problem, since everything else is relatively new.
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