Mike, Poverty;
Guys, I also get water in my engine bay as I have the sound insulation removed and when I bought the car I changed the plugs and cylinder number 4 was full of water also
I phoned the dealer I had bought the car off and it turns out they had pressure washed the engine before I went to look at the car
So I used an air line to blow out the water in cylinder 4, cleaned the Coil pack with WD40 and Electrical Contact Cleaner and refitted everything been fine since.
I do periodically check the coil packs by removing them and seeing if there is any water building up around the spark plugs again but nothing since thankfully.
When I remove the coilpacks I clean up inside them with Electrical Contact Cleaner and cotton swabs (like the ones for your ears lol) then spary a light coating of WD40 on the outside of them, let them dry off and refit them. I don't know if this helps them or not though.