car just cut off while driving. like it ran out of gas but it says i have a quarter of a tank. i put like $7 of diesel in it right before. the fuel filters are almost new. i replaced them like 2 weeks ago. i primed the system but the starter wont engage for some reason. it has done that before and i usually have to let it sit for an hour or two then it works. i have been having problems with the vacumm system. the pump went out and i replaced it with another one i had then that one went out like 4 days later. anyone have any ideas what is wrong.