My neighbor has a 2001 Ford F-150 and in the morning it starts up fine and he drives to work, However, when he gets off 8 - 9 hours later when he starts it up the rpm goes up to >1200 (high idle) then drop to about 400 rpm and then shuts off. In order to get it to go, he has to use both feet to operate the gas and brakes at the same time. Within 3 to 5 minutes it begins to run normal at about 1100 rpm. What might be the problem and fix.
The problem might be a dirty throttle body and Idle Air Control valve. It is probable that the IAC valve has gotten gummed up and can no longer control idle speed until it warms up. If it has not been done in a while, have the throttle body cleaned with emphasis on the idle air passages. If the IAC is easily removeable clean the pintle and the passages independently. Otherwise, have the IAC system diagnosed to see why it is not working as it should.
Hope that helps.
Thanks. I will pass on the information.