i have a 93 F-150 w/the 4.9 has spark at plugs has gas at fuel rale presher checker can smell fuel when cranking crankes strong runs great when you can get it started but wont start and then all of a suden it will and nuthing has changed also only hapens when she sits for a day if it only sits over night it will start w/in 3-4 turns of the motor on first try.