Check engine after engine washed and detailed

What is your question?

My alternator was killed following the detail of the engine. Managed to get it fixed but the next day it shook mildly and check engine light flashed and turned off. Next morning it shook harder and check engine light stayed on. Reading on computer was a miss in coils 1, 2 and 3. Cleared code and then the light came on again. Could the water have damaged the spark plugs? I just want to make sure it just needs to air out because water hit something or if this is common for my car at 108k miles. Thanks!!!