Is there some sort of boot that covers the distributor to keep water out? I've changed cap and rotor and wires, but still can't drive in the rain. Even after it's rained and the car is parked it won't start. Once it's wet, it's a 24 hour process to let it dry again. Maybe it's not water in the distributor, am I overlooking something?

Well, there are still other problems like a coil wiring problem or whatever. But I would personally yank the plugs and make ABSOLUTELY sure they are between .028 and .032 inches of gap.

That's almost a guaranteed fix for 99% of "my car won't start when it's wet". Usually the plug gaps are so far gone, a simple EYEBALL gapping will get the car running. While there are still other problems possible, I'd start with those if you haven't done it already.
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1992 940 wagon, low miles
as well as others.

Chris, I never even thought about plugs being the culprit, but that makes sense. I haven't had the car that long, and that's one of the things I haven't done yet. Thanks

Brad - How about this? When the engine is dry but cool, take a spray bottle and wet one component at a time until the engine refuses to start. Also, look at your engine in the dark, what you see might be instructive.

It would be far easier to assess one component at a time than to hope to find the offender among many possibilities.

I would suspect the coil wiring, coil wire, power stage, suppression relays, or crankshaft sensor.

Look at the FAQs to make up a list of suspects.

Your problem could even be as far away as the fuel pump.

The cover on the distributor might be for water, but my old-timer advisor tells me to discard it after it gets dirty because it hides dirt that can cause arcing.
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3 8s & 2 7s 725,000 miles total

Thanks James. Just when I thought I had it narrowed down! Good idea spraying it down. Thanks

Might want to check that the ECU (behind right kickpanel) is not getting wet. The snorkel/hood/umbrella thingy that stops water from going into the ventilation fan inlet often falls off (both of my cars :( ) allowing water to go into the vent system, where it sometimes ends up dripping on the connector for the ECU.

Haven't checked that, but i'll look. I've been searching the web looking for engine bay photos, and what I've found looks like a plastic cover over the distributor that I am missing. That's why I thought "water in the distrib."
Also, I never have any water on the floor. No wet carpets or anything.
Thanks Brad

Haven't checked that, but i'll look. I've been searching the web looking for engine bay photos, and what I've found looks like a plastic cover over the distributor that I am missing. That's why I thought "water in the distrib."
Thanks Brad