Temperature was about 100 degrees when I measured this.

Did some research on internet and found that vacuum on the suction indicates something is plugged. In my case, it is a sticking expansion valve. If I tap the valve, my refrigerant starts flowing again and I get my cold air back. Works until I stop and restart car, then have to tap it again. Funny, because I haven't located a thread here that diagnoses a sticking expansion valve, and I would think this might be more common.

A new expansion valve only costs about $30 - but the real cost is going to be in the R12 recovery and recharge since I don't have a recovery machine. I will call a couple of places tomorrow to find out what they'd charge for this. Until then, I'll keep tapping my expansion valve!

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Treiberg's Collection: 1981 240D, 1985 300SD, 1992 300E, 1997 E300D, 2005 C230K