Ya, it isn't exactly "illegal" to wash your engine bay, but definitely know what you can and can not zap with water. I usually give the engine bay a once over every time I give her a bath, and every few times I will use an spray cleaner in there that sits for 15 mins before spraying off with water again. Never had any problems, but it also pays to know what NOT to get wet or over-saturate, heh. Totally needed after winter ends here to get all that salt out of there.

And for the love of God, do NEVER use a pressure washer in there, heh. That isn't exactly "illegal" anyways, but it probably should be.