Hello, recently my 2004 expedition got water in the oil and had a seeze, took to shop who fixed the hose that was leaking water into the moter , did a oil changed and additive ( lucus ) and all seems to be running ok with a minor knock.. Shop said that no bearings were spun , but may be worn some. Truck does seem to be running ok , however once its warmed up the oil pressure gage drops to nil at idle , once RPM get about 900 pressure comes back to normal.. could the sensor be messed up , or is there anything that would have triped in the computer when seezed that needs re-set? I realize that i will most likely need to swap motors eventually due to the worn bearings , but the shop said that should keep running as long as we stay on top of oil and additive ... just wondering about the low pressure at idle ... please advise / opinons ...