just for future reference, when you go to pressure wash your engine again, do this.
take the cap off, put paper towels inside of it, close it back onto the distributor, then cover it with a plastic ziploc bag & either some wire, zipties, or even some string, to tighten the bag down over the capr & distributor.. Just remember to not hit it directly onto the bag, cap, etc. otherwise the same problem will arise. Also, don't forget to take the paper towels out, either.