Ok, so I have a 1995 T/A 100k miles exactly... I have always been so proud of this car because it NEVER EVER missed a beat once..ever. I had a LT1 Firehawk that was a nightmare... anyway... on the way home from work, I smelled cooland strong coming from the A/C... I got scared thinking the headgasket blew.. so im driving home slowly... get into it just a bit in 4th gear.."A4" and sure enough it missed. Got home, looked on the pass side floor and sure enough the heater core was leaking, thank god. I bypassed it since summer is coming in Houston, and will fix later. After that, the car started missing worse and worse the next 2 days, either in closed loop or open. I get under the car while its running and reach for the closest plug wire I could. I pulled the plug off the spark plug on the #1 cyliner and the idle did not change at all. Pulled off the # 3 plug and the car stumbled and the boot was arching out nicely. The #1 plug was not arching at all, zero spark. I replaced the #1 wire with a new one I had. Same result. So I guess my question is... could this be the opti for sure? Car got way worse in just 24 hrs it seemed. Would the opti going bad not give spark to just one plug wire? The coil wire is new. I already ordered an opti and water pump, but I want to make sure I diagnosed this correctly. So once again, no spark from the #1 plug wire while the car is running. Made sure it is plugged into the opti all the way... Im not new to the LT1, but its been a while since ive had to diagnose a problem on it. Either ice cold,open loop, to heated up closed there is zero spark to the #1 plug wire... thanks a lot guys!!!

 

Wouldn't a fouled plug also not have any spark? Did you pull any plugs????? Put a known good plug on the NEW #1 wire and check it for spark.

FWIW the #1 and #2 contacts are at the bottom of the opti so if it got contaminated with something, it would tend to collect at the bottom.

You should have pulled plugs first and then the cap second. Before you started ordering parts.

 

Did you find the problem? Mine is doing something similar.