The over-voltage relay provides power to the fuel system computer...any problem & the engine will be difficult to start..

ALL of the other problems sound like battery..battery cable...or ground problems with the chassis ground!

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MERCEDES Benz Master Guild Technician (6 TIMES)
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44 years foreign automotive repair
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190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
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