HomeAll RepliesReply To: Pre-start and post shutdown noises Reply To: Pre-start and post shutdown noises Sponsored November 14, 2022 at 10:59 am #734089 X31_1500Participant When you walk up to the truck with your FOB in hand and open the tail gate, or a door, the fuel pump charges the primary fuel system for the start up process of the engine. Sponsored Subscribe to GM Authority For around-the-clock GM news coverage We'll send you one email per day with the latest GM news. It's totally free. First Name Last Name Email Address Subscribe via Email Leave this field empty if you're human: Sponsored