4.3 GXI-E starts up fine. As it runs a bit the fuel pump will make a whining sound and feels like it's vibrating on the right cylinder as you look at it. The engine then sounds like it starves for fuel sputtering and backfires. It may do this for a minute or so then it will rev up and settle back down to a normal idle until the pump does the same thing. I've checked the fuel filter for water and it's ok. Are there any tests to do or am I looking at a pump? Are there any electrical issues I may be dealing with? Thanks for any help
