Steve,
When you said you have seen many 4 cylinder failures because of the controller, did you mean the electronic control unit( $800)?

I am running out of ideas. The car has spark, fuel, new trigger points and correct timing, how can 4 cylinders not fire?

Is the ECU kaput? Maybe 4 or more valves are shot. I appreciate all the help I receive on this forum, but so far we have not found that gremlin. Thanks -Mike

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1973 280SEL 4.5