After work I park my truck and sometimes when I try to start it after work it almost dies. It might be because of the incline and the fuel no getting to the engine? well today I started it and I waited then I put it into reverse and it died, I tried starting a couple times but it felt like the whole truck moved but wouldnt start, I waited about ten seconds and tried and it started? any ideas? 300 i6 1993 f150