I have a 93 3.0l xlt, all of a sudden when you switch it on fuel pump cuts on but will not shut off after charging system. Under these circumstances cel stays on while trying to start engine. Every once in a while, switch on fuel pump shuts off after 2 to 3 seconds truck fires up with no cel on while cranking. These occasions are few and far between. Bumfuzzeled in SC, any suggestion will be greatly appreciated.