My check engine light is still on n

What is your question?

I've replaced the fuel feed line, fuel filter, gas cap, fuel filler neck hose, fuel tank vent hose, and after every application I do It stays off a little longer each time however it still comes on and I'm not sure where to look next, the vacuum line to the fuel pressure regulator has a good suck and idle didn't change any, no fuel residue inside of the vacuum line, and the fuel pump itself doesn't sound like it's got any issue, however I have a feeling that there may be a pressure leak due to a slight fluctuation in the gas gauge, and a very faint fuel smell, maybe a bad gasket/o-ring around the fuel pump?

How long has your 2002 Ford E-150 Econoline had this problem?

Been making attempts to fix for five months