All,

Our 1993 (M104)engine has begun to suddenly die, under a variety of conditions. Symptoms are: 1. ASR light illuminates and tach goes to zero. 2. After the car slows down, all warning lights on the dash illuminate, and oil PSI goes to zero (i.e., the engine speed has dropped). 3. Car can not be immediately restarted, but can always be restarted after waiting 5 to 7 minutes.

This has occurred at steady-state cruising, moderate acceleration, at idle and while decelerating. It has occurred with the A/C both off and on and with the radio off and on. It has occurred on very smooth roads (and at least once, at a full stop).

The Over Voltage Protection Relay was replaced a year ago. The electronic throttle (ASR) was also replaced about a year ago. The car has just come off a major service and the motor runs great, when running. (Problem surfaced prior to the major service).

This will be difficult to troubleshoot, as it occurs intermittantly -- sometimes hours apart; sometimes minutes.

I am, for the moment, ruling out fuel delivery, as the tach goes to zero the instant the ASR light comes on (and power ceases).

Any known weak components in the electronic ignition system (HFM-SFI)? Ideas for troubleshooting?

Thanks,

Alan

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Alan