i have a 1996 explorer with a 4.0l, V6. Runs fine, if i drive it for 1/2 hr. or so and shut it off, it restarts fine. If i let it set 15-20 min. and try to restart it, it will hit, spit and sputter but will not start and run. If i keep trying it it might start and when it does it runs smooth. No codes are generated. Need help. thanks mike