oil pressure

[xt master]

I am having a new problem.when idling the oil pressure some times will drop to zero.if I rev the engine a little it comes back up.is it the guage or pump going bad.what type of pump does it have.2.5 l 97 tj

 

[SteelHeadz]

The oil pump in the 2.5 is a positive-displacement gear-type oil pump is driven by the distributor shaft, which is driven by a gear on the camshaft. Oil is siphoned into the pump through an inlet tube and strainer assembly that is pressed into the pump body.
The pump incorporates a nonadjustable pressure relief valve to limit maximum pressure to 517 kPa (75 psi) In the relief position, the valve permits oil to bypass through a passage in the pump body to the inlet side of the pump.
Oil pump removal or replacement will not affect the distributor timing because the distributor drive gear remains in mesh with the camshaft gear.
The MINIMUM oil pump pressure is 89.6 kPa (13 psi) at 600 rpm. The MAXIMUM oil pump pressure is 255-517 kPa (37-75 psi) at 1600 rpm or more.
If the oil pump is failing and lacks the pressure at idle, you should hear a knocking sound and if thats the case, you shouldn't run the engine until you replace the oil pump. I would start by verifying the true pressure by installing a manual oil pressure test gauge on where the oil sending unit is attached to and monitor the gauge for the minimum and maximum pressure. If it's good, i would replace the sending unit switch.

 

[xt master]

Thanks for the info.when the guage dropped the engine did not seem to run any diffrent or make any more knocking than usual.I have always had a small lifter tap but nothing magor.

 

[Dirt Toy]

Thanks for the info.when the guage dropped the engine did not seem to run any diffrent or make any more knocking than usual.I have always had a small lifter tap but nothing magor.

if you running light weight oil like 5w30w or 0w30w you can have low pressure that would not register on stock oil gauge at idle

I had a problem where my oil pressure sensor wires were exposed and if they got wet then i would get engine error code of no oil pressure.

 

[Mikekaz1]

Yeah my '00 TJ dies the same thing. But it runs perfect no change, no knock nothing. I just did an oil change and put slightly thicker oil in it. After I drive around a lil ima see if it still does that

 

[xt master]

I run 10-30w oil.

It has not happened again since that one day.I am thinking a bad connection some where.I have a few electrical gremlins.13 year old wiring in a northern state with all the lovely salt in the winter time has done some damage to my wiring in other areas.