This humming sound has been going on for a while now, and its starting to irritate me. It only starts up when I drive for an hour or so, if I drive short distances, I hear nothing. I dont feel performance loss or anything funny. When the humming starts up it becomes more high pitched when I accelerate, and I can hear when idling. It sounds like its coming from the rear of the Jeep but I haven't been able to figure out where its coming from, I dont want to spend 200 bux on a new fuel pump if i dont need it. I never have trouble starting the car.
03-12-2013 02:57 AM
Buy a cheap mechanics stethoscope with the metal probe. Maybe 20 bucks at auto zone or pep boys. drive the jeep till your noise starts. Pull to a safe place. Leave it running with someone to keep the parking brake on. Slide under the rig and poke around with the probe. You should be able to track it down if it does it at a stop. If it does not do it at a stop then it's not the fuel pump. The pump only knows idle not in gear, out of gear.