Interesting... Oil Pressure Gauge increases with Electrical System Demand???

[rxdevil]

Hey everyone! Long time reader, first time questions asker. So this is my latest ??? with my 1996 Explorer XL.
When I crank my stereo, my oil pressure gauge jumps up and bounces. Now, I'm used to the Volt Meter kinda doing this, but my oil pressure gauge? WFT?
It is a stock motor, stock alternator, stock wiring pretty much.
I have both a 500w sub amp (alpine), a 400w 4ch amp (focal), great head unit, and great speakers. This will pull a bit of power I know, but the oil pressure gauge???
This is a bit worrying due to the fact I don't know if I can trust my oil gauge.
Any suggestions or thoughts people?
Thanks
Myles
Edmonton, Alberta, Canada

 

[Turdle]

Yeah your voltage is going low. Lower voltage to the gauge =incorrect reading. That is how a sender works.
You might have a battery cable issue as well as not enough alternator.