I have a 1999 H.R. Navigator with a ISC 8.3 ,350 Cummins. I went out to start it to drive it some and when I turned the switch on the STOP and WARNING light came on and went off then the WARNING light came back on before I cranked the engine. I started the engine every thing looked normal ( Pressures and Temps ) I drove it about 15 miles then stopped and had some one read the codes. it said there was no oil pressure but idle cold was 75 PSI, running warm 38 PSI, and driving around 43 PSI. So with this said does this engine have 2 oil pressure sensors one for the ECM and one for the gauge cluster or do they share one sensor?