bad gas, flushed lines and replaced spark plugs and wires, wont start, backfire

yes, a small bit. we bleed the fuel lines until good gas smell came out and changed the fuel filter, but still it wont start. then we replaced wires and plugs; still the same symptoms, it acts like it isn't turning fast enough. It tries to start then backfires and coughs. kept battery charger on during these trials so as not to run battery down. A week before, the check engine light came on for 3 days then my husband adjusted the o-ring and the light went out, but I fear there is some type of emission problem or other electrical. We plan to change the regulator and orings tomorrow. Any suggestions?

Only thing I can suggest is a compression test and recheck plug wire order to make none are crossed up... Strongly suggest compression test!!

took out the injectors, and three of the injector holes were standing in fuel, is this ok? I didn't want to go further until I was sure this does not indicate a worse problem.