That part is called the Fuel Pump Ballast Resistor. It's purpose is to lessen the voltage getting to the fuel pump and thus lower the fuel pump's speed and thus lessen the noise it puts out. In 87 Jeep had a bunch of complaints about the fuel pump noise and the resistor was their fix. Usually when the resistor goes bad, the truck will fire up, and then die in a couple seconds as the computer switches fuel pump power from a direct line over to the resistor. But now that you've said it, it sounds perfectly plausible that it could be the culprit in trucks with poor fuel pressure. Thanks! :thumbsup: