LS1 Oil Pressure Problems

[cchatfield]

I was hoping someone on here would have some information that could help me pinpoint a problem.

We own a 2004 Response with a LS1 Corvette engine. At the end of last season, we had the boat out and all of a sudden, the oil pressure gauge dropped to 0 lbs and the Oil Pressure warning beep came on. We immediately pulled the throttle to neutral and the pressure picked back up. It did not go back to 100%, but it fluctuated at a lower than normal level. When we put the boat back in forward above an idle, the pressure dropped again. We weren't that far out, so we drove it back in at an idle. When we called a Malibu dealer, the dealer said it was the Oil Pressure Sending unit and sent us one to install.

We installed the new sensor and when we took the boat out at the beginning of this season, a different beep came on that was constant and beeped the entire time the engine was on. The gauge showed a normal pressure, and the display did not have the oil pressure warning signal. However, when we disconnected the wire from the Oil Pressure sending unit, the beeping stopped. Tried replacing the Sending Unit with another unit and the beeping did not stop.

We decided to ski this weekend since the gauge still seemed to work and we would work on the problem next week. However, the original problem started back up towards the end of the weekend. We were towing a skier and the pressure dropped to 0 lbs and the oil pressure warning beep came on. When we dropped it into neutral, the pressure picked back up but at a lower than normal pressure. We rested the boat over the night and tested it out again the next day and the pressure was back to normal.

Does anyone have a clue what the solution could be to either the constant beeping that occurs when the engine is on or the sporadic, fluctuating pressure on the gauge. My next adjustment for the beeping is probably going to be the Oil Pressure Switch, but I'm more concerned about the fluctuating pressure.

Thank you

[SmoothWaterMan]

There is an oil pressure switch that signals the ecm to sound the alarm, and the sending unit that sends data to the gauge. It could be both were clogged/bad/etc, but it's always good practice to install a mechanical oil pressure gauge and see for sure in your situation.

Peter