God this is a common thing... I did the sme thing to my 380SE euro and tried to start it. No start. Waited a little bit and it started but stumbled like crazy and ran on an odd number of cylinders. Come to find out that when I got it running the water cracked the coil wire tower on the Dist cap. Do be weary on a thorough engine wash...

Back in the old days, we always sprayed WD40 in the distributor cap and it worked.

I am terrified of water damage on something that would take a long time to diagnois...not to mention the pain of getting what ever was needed to replace it...especially on my 500 SEC...

Whenever I power wash my engine, I use a plastic bag to cover the distributor cap and any other sensitive electronic components.....