Having a problem with my 1993 corvette. I have a crank and no start problem. This is what I've done so far:

Tested fuel pressure at rail. At the 2 second pump prime pressure at 40psi. Will slightly drop to about 35 after waiting for about 5 minute. During crank pressure steady at about 40psi.

Hooked up a noid light to an injector, cranked and light flashed. Did is to 3 injectors and all looked good.

Checked IAC and was operational.

Unplugged a spark plug wire and placed it near the block. Cranked and did not see any spark from wire to block. Did this with 2 plugs and no spark.

Testing the coil. I couldn't take the plug off of the distributor so I took the plug off the coil. I attached a wire to the coil and placed near block, cranked and got spark.

Will try and test the actual plug wire that goes from coil to optispark. But I believe that plug wire is good. Only 1 year old.

History: July 2017 I replaced the optispark with a new Petris optispark. While in there I put in a new coil, ICM, plugs, and wires. Great improvement in performance. Did notice that I got a code 16 in module 4 when jumping A and G the day I did all that work. Was concerned but car ran great even though the code 16 remained for all this time (1.5 years) after installing the new opti etc.

Any help appreciated.

Thanks
Tony