It sounds as if you are having a common problem. I would have the overvoltage relay checked, and the fuel pump relay checked. Also I have seen the connector for the CIS-E control unit fill with water and cause a simmmilar problem. This happened when the plastic cover was missing from behind the battery.

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Benzmac:
1981 280GE SWB
1987 16V
ASE CERTIFIED MASTER AUTO TECHNICIAN
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