OIL PRESSUE GAUGE DROPS DOWN TO 0 AND BACK UP TO NORMAL ALOT , BUT THE RPM'S DOEAN'T MOVE AND THE CHECK ENGINE LIGHT ISN'T ON ??????????????????????

 

The oil pressure sender is nothing more than an ON/OFF switch, or diapram contact switch.. With engine oil pressure,, the switch is 'Closed' indicating Normal pressure through the cluster, when 'Open' indicates low/no pressure.. Try gounding the oil sender harness connector and the gauge should then read normal.. To verify a good/bad sender, with the engine running, test for a good ground signal through the sender terminal/connector to block/ground ect.The sender/harness wire is WH/RD single wire connection..