You are suffering the same symptoms I am.

I normally get 40F out the vents on a 95F degree day with 90% humidity (excellent) running on the highway. 50-55F at idle.

I am getting codes 5 and 6 in pin 8 of the diagnostic module.

You probably have the same.

In my troubleshooting, I changed the tensioner as well as the belt with no success.

I was observing the compressor cycle at idle, it was cycling fine. At about the tenth cycle, I noticed the clutch would start slipping and then stop (not engage, and A/C stops working) AHA !!

I think the clutch material is either wearing out, or the gap should be adjusted (in my case). I have not done it, but now I know why the A/C stops, sporadic clutch slippage.

You may want to check that.

Pedro

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1999 Porsche 996 Carrera Convertible
1994 420E - SOLD
1986 300E - SOLD, what a car
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