99 mercury marquis
let it dry out.
You have individual ignition coils on the spark plugs. You can either remove and dry them one by one. Or as Kelly said let everything dry out. When washing the engine you need to cover these coils so they don't get wet. Once everything drys out it'll be fine. HTH. - Jim
Don't wash engines on 21st Century cars- do you realize what complicated electronics are under those hoods?!
When it dries out it may or may not be fine. Worst case is that you will have to buy an ignition coil or two. Be careful when washing an engine with coil on plugs and don't direct the spray directly at where the plugs and coils reside. Also washing a warm (not hot) engine is helpful in that the wash water evaporates faster.
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