On Ford products with IAC (a.k.a. bypass air) solenoid, a gummed up one can lead to a “no start” condition.
If customer complains of crank/no start, and especially if they smell raw fuel, have them wait 10-20 minutes and try again. If the engine does not immediately start, stop cranking, hold the accelerator pedal to the floor and start cranking. While cranking, slowly release the pedal. If it starts, it is likely a gummed up IAC.
Remove the IAC and clean with carb cleaner. Don’t waste your time cleaning the inside of the throttle body. Ford actually coated the inside of the TB with something that looks like sludge (but is harder) so that no air goes past the TB plates at Closed Throttle.