Thanks for everyone's help on the CCU - the CCU and servos work.

Here's the funny issue (now). When the temp. is hot (97F+ and sunny), the A/C only works intermittently and today I was sweating my rear off. The compressor will cycle and sometimes it's cool, mostly it's warm.

When the temp. cooled down this evening (80F and not sunny), the A/C works great and the compressor stays engaged. I can actually cool off inside the car and get comfortable.

Now from what I've read from here and Pelican, there's a chance the R12 level might not be up to snuff and the pressures are incorrect. I mean yes, the compressor does engage so I know that it works in that capacity. But without working A/C during the daytime, the 911 is near-unbearable to drive.

Any advice? I've the correct refrigerant level figures, but what are the correct high/low pressures?

 

Do you have access to the factory service manual? It has a refrigerant pressure table for both R-12 and R-134a. The desired pressure varies depending on the ambient temperature.

 

is the condenser freezing up with high humidity

 

My dad took it by the shop today and it turned out the compressor is leaking. Pity. So a new compressor and condenser (from what I was told, I may be wrong) are being installed and the system converted to R134a. It would make top-offs a breeze as R12 is becoming more expensive (and requiring licensing to purchase).

So we'll see how cold the A/C is tomorrow around noontime.