I just installed a new optispark. The car runs a little rough. Did scan and got P0300. My code book says , Random cylinder missfire detected. Now for 96 LT-1 what should I do ? I don't have a service manual.

 

My LT4 did the same thing--I found out the coil wire was shorting out on the backside of the water pump where the coil wire goes into the optispark. Replace the wire. The boot on mine was split, but you couldn't see it until the wire was removed and the boot was twisted by hand, and then it appeared. It was about a 1/2" split about 2" up from the bottom of the boot. When I put the wires on the Opti, I even ohm'ed the coil wire, and it showed it was good, but the split was undetected.