Ive noticed that it misses every now and then when Im sitting at a stop light, sometimes it surges too. Almost to the point where I think its going to shut off. Rpms are around 700 before it starts acting up and Ive seen them as low as 400-500. The truck starts fine cold but when hot it cranks alot longer than it does when its cold and when it fires it revs up to 1200 rpm and drops right back down to 700ish. Right now my fuel filter cap is leaking a little im waiting on my billet cap before I replace it. Would this cause my issue? Do i have a HPOP going bad?