Oil pressure gauge problems

[crdickey]

My gauge frequently pegs above 80 psi, even at idle.

With a hand held direct mount it reads normal, 40 @ idle and 70 @ running speed.

'03 PS-197
Preditor motor
51 hours

The dealer has replaced;

The sending unit
The MMDC computer
The gauge
Installed a better ground wire

Any ideas?

[morkinbc]

I am having the same trouble.I have replaced sending unitI also have no amp gauge.My check engine light is on and the engine is in limp mode.I have ordered mmdc box.I hope this cures my problem.
Cheers
Mork

[BrianB36]

any sending unit I've come across works off of ground as sensor by-metal is heated the ground strengthens an oil descending unit works opposite if oil gauge stays maxed out may have ambient ground trouble meaning any after market eletronics installed they may have taped into the wrong ground