OK, new problem. Yesterday I had the car out for about 20 minutes of active driving for the first time since starting the major 7 months ago. I took the motor up to 6500 RPM and kept revs around 3000. The car performed well, no smokes, no leaks. It was idling a bit low at 5000 but smooth. Today I vacuumed out the AC system, and while charging, after about 10-15 minutes the car stalled. With the AC on, the idle picked up to 1000, the vent temp came down to 60, the ac condensor and radiator fans came on as they should and all seemed well until it died. No fuel, no spark. I guess the ECU's did not like something? Checked all fuses - OK Unplugged and replugged all connectors on the relay board - NADA I checked the Motronic diagnostic and I got the usual code for the "catalyzer" on the 7-12 bank, and then just rapid, steady short flashes with no pause. On the 1-6 bank I got the catalyzer code and then the RPM sensor code and then no more codes. I unplugged and replugged the RPM sensors - no change. I also noticed that the cabin AC fan was not working. Any ideas on where to go next? I will check for 12 v on ECU pin 27 tomorrow.