I recently had to replace the compressor on my 911 after many years the nose seal started to leak, and I know the compressor was getting worn.
To really test the cooling, it needs to be hot, high 90s and full sun. We have yet to hit 90 in OKC this year. I keep waiting for a good hot day to go for test drive to make sure the pressures are ideal. Hard to do that when it is in the 70s.
Went for a test drive in mid 80s and was about to freeze to death in the car.
With the fan blowing at hurricane speed, the little tiny vent was down to near freezing.
I sure hope we can get to some 95 or hotter temps before my trip to Palm Springs. That will test the AC, but no way to tweak it on the road.
The return line is certainly keeping the compressor cool.