Turns out the problem with my C4 is Opti-Spark. Ugh! After spending the money to have the ignition control module and ignition coil replaced, I can't say I'm exactly happy to learn the problem remianed and turns out to be Opti-Spark -- another $1,400 to repair. Sigh.

What's rather troubling is that the guy I bought this 1994 Corvette from a little less than two years ago had the Opti-Spark replaced only about a month before I bought the car. He didn't have the work done by a Chevy dealer, he had it done by another mechanic he used periodically so I don't know whether GM parts were used or if they were aftermarket parts, but it's troubling just the same.

Does anyone know what would cause the Opti-Spark to fail again in less than two years time?