92 GMC 1500
My truck won't stay running unless I'm
pressing gas. It won't start. Got new fuel
pump cleaned filter what could it be. I lost
gas cap could that do it
Without a gas cap I'm surprised it doesn't have the check engine light on. Get a gas cap on from junk yard or parts store. If you cannot pass emissions, spray a pinch w d 40 under gas cap and put back on. Hope it helps.