I'd suspect that on an older engine, but this one is all electronic and has no distributor.

I fitted NGK platinum plugs not long ago, and Magnecor 7mm leads which run (mostly) under a weather cover. Given that this engine ran smoothly on just five cylinders when I first got the car (one of the leads had popped off!) I don't think it would be as dead as it is with just damp. I will strip down the ignition system, though.

Rob