Okay so, at first I had no oil pressure whatsoever in this jeep. That's the way i got it, she runs great with no metal in oil. I replaced the oil pressure sender today, as she started up the gauge went down to the bottom and back up to as far max as possible. The gauge wouldn't move before, so I know that I'm at least getting somewhere. But I still am yielding max values. Any help?

 

Get a mechanical gauge and try it.

 

You sure you got a sender for a gauge and not an idiot light?

 

I get the same thing on the ZJ, max reading. I am suspicious of the quality of calibration on the senders. Current sender is APC, offshore mfg. May try Napa or Chrysler next, need a made in USA quality sender. Good news is you see pressure and not a zero reading. Less likely the pressure is maxing our gauges at 75 plus psi or plus 5.4 bar is you have a metric gauge. I do see over 60psi on the XJ at road speed when fresh oil change, drops to lower 50's when oil is well used, 22 - 30 at hot idle.

 

if the gauge pegs out with the key on engine off then theres a short in the wiring, i think short to ground but id check a wiring diagram to see if its power controlled or ground controlled

 

im having the same issue right now, oil pressure is at 10psi and rarely goes up but 90% of the time its low

 

The sender is significantly smaller than the old one. And the thing that really gets me is that the old gage had a .040"snubber hole on it, the new one does not..i think the dummie at the parts counter gave me an oil pressure sender for an idiot light.. or it could be wiring, if it is a resistance type sender then an open would explain max readings.. I would post some pics of the old and new senders, but my droid isn't doing it. Thanks for the quick feedback guys

 

you my friend have yourself the wrong gauge sender unit. it should be about 4 inches long and have a plug type connector on the end of it

 

^^ X2