Cooling issues over time

[Al9]

Really strange that the suction would get so low as to trip the suction side pressure switch (if car comes with at least one, that is) only after 10 minutes and not immediately.

I once had an issue with my car's AC where the compressor started getting noisy only once the thermostat opened and the engine radiator got hot. After some serious tinkering around, including a new compressor and expansion valve (old ones had some issues anyway and replacement parts featured some major redesign, such as a different, 100% metal, compressor clutch hub, and a thicker exp valve actuator rod), it turned out to be a severely worn radiator fan motor. Barely working enough to never trip the ECU into disengaging the clutch (only with the old worn compressor in place though), yet causing noisy compressor operation and feeble cooling in hot sunny days.

How much does the engine coolant temp affect AC operation?

[Cusser]

I have noticed when this does happen the compressor does appear to have stopped so perhaps i could try that with the indicator light even if it is just a temporary addition to see what is going on.

Yes, would be of GREAT value to know if the AC clutch is getting voltage when the drive plate (center) stops turning.

[bazzybtec]

How much does the engine coolant temp affect AC operation?

the temperature is sitting where it normally is and the issue seems to happen well after the engine reaches the operating temperature.
The air is pulled through the condenser first then the radiator.

[Cusser]

bazzy - you stated that the compressor drive plate stops turning after a while. I suggest to concentrate on THAT.

[tbirdtbird]

Agree.