Yeah, an event that has happened 3 times in the past year would be hard to diagnose if it couldn't be reproduced for testing purposes.

Out of curiosity,

Does your car have the original engine wiring harness?

Does your car have the original OVP (over voltage protection relay)?

What plugs are you running?

Have you ever replaced your coil wire resistor boots?

__________________
Paul S.

2001 E430, Bourdeaux Red, Oyster interior.
79,200 miles.

1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".