I have a expedition 4.6 L (W) i just purchased. I took it to a back yard machanic who said the engine needed to be replaced. The vehicle runs great and sounds great for the first 10 minutes or so. The the oil pressure gauge show the oil pressuring dropping kinda like a rod with a fish on the line ( tap, tap ). If I cut the car off and back on the oil pressure gauge resumes to proper level. Eventually it the oil pressure will drop again. I dont believe its the guage because when the pressure does drop, after a while the vehicle does begin to knock some. It sounds kinda bad but it still run ok with plenty of power when I'm experiencing the problem. Can someone Help?
Jan 30, 2009 at 11:57 PM