Will contamination in my fuel tank cause the vehicle to not stay running

1995/S~10/4.3 liter V~6/ Chevy Blazer:First displayed signs of gettin low fuel pressure, and would only start if primed, but wouldnt remain running w/o footfeed that maintained 1.5 RPM on the tack. Anything under that, it would stall out. I put a pressure tester on it and it read a solid 62psi. So then I replaced the fuel filter. The darn thing started up ran great and idled while maintaining 62PSI on tester. After about 10mins it stalled out wouldnt restart w/o priming engine again & refused to idle once more, but this time as you use footfeed to keep it running it begins to backfire while throwing a six inch glowin~red~flame from the tail pipe and eventually stalls out. But now it stalls out at 1.5RPM on tack, and you have to prime it all over again to restart. Allfuel system parts check out to be good. Fuel sys psi is fanominal. I just cant get over the fact that after replacing the fuel filter all symptoms STOPPED & the darn thing ran GREAT for 10minutes and started up fine w/o having to prime it. But then stalled out died and refuses to start w/o priming once again and backfires the entire time throwing a red six inch flame out the pipe until reaching 1.5 RPMS and then stalls out and wont start w/o priming? I SCREWED! Im on a time sensative scheedule! Its been not running right for a while now. PLEASE HELP! OPEN TO ANY & ALL SUGGESTIONS. Im so ready to lite it a blaze and roast hot~dogs over it! LOL! J/K (Please respond ASAP!) Thank you