Normally I don't, but I have when time was an issue.
I raise the hood to allow the engine heat to escape. vacuum the interior, spray the wheels which are usually relatively cool by then, clean the tires, wheels, wheelwells.
I then close the hood and do the remainder of the vehicle.
My normal wash would include a bucket wash of the engine compartment at least once a month. If the engine is still hot, I would probably just use a wet towel to wipe things down under the hood.other times seems to keep thing looking new. I do try to do the engine compartment wipe down every wash. On my own vehicles, I find it is much easier to keep them clean than it is to clean them when they are really dirty.
Unfortunately you won't always be able to have that choice as a professional.
Charles