2000 Regal 2150 oil pressure gauge pinning

[Deciball]

Help please! I bought this boat without testing, relying purely on the seller's word.... I know, it was stupid. Now I am trying to take care of all the issues and one of them is the oil gauge needle pins to the right as soon as I turn the ignition switch on, even before the engine starts. I replaced the oil pressure sender unit with no difference.Any advice would be greatly appreciated ESPECIALLY from those who has experienced it.
Thanks everyone!

 

[Silvertip]

The "s" terminal and ground terminals are shorted at the gauge or the send wire is shorted to ground.

 

[Deciball]

Thank you, I tried to ring out the shorted connections but so far to no avail, can't find a short but will keep trying some more today.

 

[Silvertip]

Disconnect the sender wire from the "S" terminal on the gauge and see if the gauge now zeros with the key in the run position. If it does, the sender wire is shorted to ground somewhere. If the gauge still doesn't zero, the problem is at the gauge. Check the mounting bracket to make sure it isn't shorting the "S" terminal. Also make sure the ring terminal for the ground terminal has not swung around and is touching the "S" terminal. The "S" terminal also needs to be isolated electrically from the gauge case and any other grounded objects. If insulating washers are used make sure they are installed properly. If all of this checks out, the gauge is probably shorted internally.