Ok the other day i was sitting at a stop light and when i went to hit the gas as i took my foot off of the brake i noticed a humming sound i guess you could say thta was rather loud, when i gave the truck gas it seemed to fade out and go away. It doesnt do this everytime but enough to tell me something is wrong and enough to bug the heck outta me. Does anyone know what this could be. oh if i just sit there and dont give it gas it will keep making the sound. Might this be the fuel pump acting up because of the cold weather its about 15 on avg. here now. Any help on this will be very appreciated