Chainsaws in Climate Control: A Guide

"In my Polo with manual air conditioning, the engine has recently started making a slight sawing noise when the air conditioning is turned on immediately after a cold start. However, the compressor clutch is definitely engaged the entire time and the compressor is also running."
The cooling performance is also fine so far.
This behavior does not occur when the engine is warm, and likely also not when the climate control system is partially warmed up.


Can a borderline amount of refrigerant, just above the emergency shutdown threshold, trigger this behavior? Overpressure is unlikely, as the air conditioning system has been working perfectly fine until now.

Unfortunately, the air conditioning system in the Polo cannot be diagnosed.

Ideas are welcome at any time!

Dirk.

Small update:
After checking the data logs, the temperature sensors appear to be working correctly, and the idle voltage is within the range of -0.1 to -0.5. Today, I re-examined the glow plugs. The engine isn't pre-heating in this weather, but I wasn't sure how a faulty glow plug would affect the afterglow process. Regardless, they all appear to be in good condition and are working properly.

Does anyone have any ideas?