I actually rarely use dawn for the engine bay cleaning. Maybe once a year if it gets bad. I can usually maintain it between washes by simply wiping water away and spray detail to shine things up.
It's very easy to not get dawn on the areas I don't want though. It's called laying down towels over the fenders
. Again the spray bottle is very very controllable I really don't need the towels it's just a precaution.
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Airaid CAI | Borla S-Type Catback | Amsoil 10w30 and MTG Trans. Fluid
382hp 387ft/lb | 1/4: 12.9 @ 112mph