Remember also that preflight refers to checking for conditions conducive to carb or induction icing---yes I know the caveats due to the adiabatic cooling which can take place with ALL induction systems, but still, icing can take place in newer aerodiesel if the specific humidity is high enough and the cooling in the induction circuit is sufficient to reduce the temp to freezing. but as you know all GA planes with boots or a hot wing is certified to linger in known icing for hours!
