HI , I have a 90 full size Bronco and it is having oil pressure issues. After driving about ten minutes the oil pressure drops to zero and begins to knock. Really weird, I replaces the oil presure sennsor and it went farther but still droped off. If i disconnect the battery for a minute it corrects, for about ten minutes and if im drviving and kill it then restart it will((reset??)but it will eventully drop again.If it was just the gauge i would not be alarmed but because she has 210k on her, well... Let me know if any of yall have any ideas.. oil pump, a screen maybe.... or whatever... Thanks