1997 Chevy Truck Wont Start

Engine light came on a few times but went off. In past seems to have a fuel pump problem. Was changed a year ago including filter when light came on and wouldnt start. Ran fine for a year or so. Seems to do it
when its damp out but may be coincidence.

It has a Dist Cap that has the 4 wire on each side. I questioned if it was cracked. How does it come off?

It still doesnt seem like its getting fuel. My son changed the pump for me but didnt get the over flow hose reinstalled. I thought he said he plugged it off to the tank. If its not or has an air leak to the tank will that shut down the fuel? Some one told me to check the gas cap for that reason but didnt know if that would cause the problem.