Starting issues
Thanks
Ok, this happens to F-150's and probably your starter has gone bad...I know it starts good and strong when it wants to but thats one of the symptoms of a bad starter, if you pull it out and take it to the auto parts store and have them test it, it may work great and jump every time they hit the switch but their machine (if it has the feature) will show a low voltage light which means an internal problem.
Ford starters require a high voltage kick and if the starter can't handle that it will start sometime and others it won't (usually right when you need it too).
A rebuilt lifetime guarantee starter should run around $50 or $60 bucks with the old core exchange.
Now before you go yanking the starter out (it's real easy on an F-150) first make sure your battery is ok....how old is it? Has it been completely discharged recently? If you're not sure either charge the battery up or take it and have it tested. Does your voltage indicator run at 13 volts or higher? as the alternator may have a problem if it doesn't and is not charging the battery #1 reason for your problem before the starter could be a battery issue. Second...are your cable connections all tight, especially the solenoid on the firewall if you have one on that year. Third thing, check your battery cables, especially the positive lead, if it is crappy looking or corroded, replace it...these are cheap and they go bad believe it or not, the get corroded on the inside and have a high resistance so they don't transver voltage good.
My bet it's the starter, put a good rebuilt one in and it will fire up every time.
F-150 runs forever (or so it seems). God bless Henry Ford.
John


