It never starts when it's raining...

Greetings, all ... My '94 Caprice wagon has been getting more and more temperamental over the last two years. It seems, generally, that it won't start when it's raining -- even if it's parked in the garage. This isn't even necessarily consistent. The starter will turn, and turn, and turn, and the fuel pump will spin up, and I will smell fuel, but I will get no spark.

The optispark has been changed, as have the plugs, as have the wires on the driver's side. Possible cause I keep hearing is "accessory power relay," but it's not obvious which one this is. For the last two weeks, since it was parked, it doesn't start at all.

Baffled.

most likely the coil and/or coil wire