Quick tip: don’t kill your BMW
Do not steam clean the engine compartment of your modern BMW. We don’t care if you are trying to sell it and want to get top dollar! This could be like some sudden death syndrome to your BMW electronics.
Decades ago, it was not routine, but not uncommon for the engine compartment of most makes of cars to be steam cleaned for various reasons. Seals were not as good in those days and cars just had more minor drips and seeps going on. Well, that was eons ago. Needless to say, manufacturing processes, the proliferation of electronic systems, environmental responsibility and laws have changed everything in our industry.
So, save the steam cleaning for your sofa, (where the popcorn and chips have fallen between the cushions).