I had the same issue end up replacing fuel filter, ignition cap, rotor and spark plugs. After replacing all these items the problem still persist. After awhile it got difficult to start. I found a post here and recommendation to replace OVP relay. I had a used one in my parts bin that finally fix the problem. I suggest find a use OVP in your local junk yard because this is expensive item to buy for testing unless someone in this forum can show you how to test your old OVP.

As you can see in the schematic, 12v Battery is supplied to terminal 30 and is fused on top. Ground on term. 31 and Ignition Battery on term. 15 operates the Relay, thus completing the circuit to supply term. 30 battery to terminals 87Eand 87L only when the relay is operated. I performed a bench test on my OVP relay to verify these measurements.

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1993 190E 2.3
2001 SLK230
1971 LS5 (454) Corvette Convertible

thank you members, i will try these things and get back with you all.