"Missing on Cylinder 4"

That's what computer diagnostic said at the local O'reilly's auto parts. I first acquired my 2002 Taco last March and it has run beautifully for nearly 7000 miles. I bought it with 175,000 miles, but the truck was meticulously cared for and didn't feel too nervous buying a vehicle with that many miles; it was a Toyota after all. Trouble hit a couple of days ago after a torrential rainfall of over an inch in 30 minutes with periods of rain during the day. I went to start my truck to go home-no problem- but then it started to miss. My first thought was condensate in the fuel tank. Added some Heat fuel dryer hoping it would remedy the problem. It didn't. By this time it had spun a check engine code with the light flashing every time it missed. A stop at O'reilly's produced the above diagnostic. Thinking it could be a fouled plug, failed coil pack, or injector, I went to work on pulling the plug on cylinder 4. Here is what I found: As soon as I removed the coil pack tube I saw water coming off of it. I removed the plug and it looked fine with a little rust on the outside-probably due to the moisture. I dried everything off, reinstalled and my Taco is running as perfectly as it did before. I guess the water coursed off the windshield in the downpours through the channels, past the rubber gasket and onto the coil pack leaking in. A rare event to be sure, but with it happening I thought you all would like to know.