Automotive Air Conditioning Information Forum

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I'm more interested in why the high side drops lower than the static pressure. That should never happen unless you're measuring wrong (couplers not fully engaged, manifold wheels opened instead of closed when measuring pressures), or there's a restriction between the compressor and the high port.

High discharge pressure and really low suction pressure normally indicates a restriction on your discharge/ high pressure side. Your filter drier / desiccant sock probably broke open and clogged your condenser. When the high pressure side is discharging into a restriction obviously the pressure goes up. But on the suction side it eventually runs low on refrigerant, if its restricted enough it’ll go into a vacuum. Sometimes restrictions can be hard to diagnose, it could be the expansion valve not opening enough. But your low side pressure would be higher, and normally theirs freezing up close to the valve.

I agree with bohica2x0. If the shop evacuated and recharged it to spec and your high side is still very low, like you're seeing now, the compressor is shot.