Started with a rough idle, then my check engine light began flashing. It would idle so rough it felt like it was about to die out. I drove it a few days like this and noticed a fuel smell whenever I’d get out. I took to autozone and it had codes for misfires in all 4 cylinders. Changed plugs, replaced main relay, and checked distributor, has spark and started a couple times with starting fluid. I had a guy come try to use his scanner but its been sitting for a month with a dead battery, he used a jump box and tried scanning but got no codes. He says he thinks its the fuel pump. Any thoughts?? I’d hate to buy the pump and it not be the problem.