Used to listen for the pump noise. But my hearing loss, and any traffic or wind noise put a stop to that. Funny how hearing loss slips away. One of those early pumps delivered enough pressure to spray the underside of the hood, but the truck was a no start. When i bought a fuel pressure gauge, found that punp was putting out 15 psi, spec calls for 50 -65 psi. Of course by that time the reciept had vanished. Right now truck is running great for its 211,000 miles. Just made a 150 mile trip pulling a car trailer.