oil pressure drop

    last night i was driving along and my check gauges light came on. looked at the oil gauge and it was reading 0. shut it off turned it back on and it was up again but at idle it was just under the 20 line. when i would drive it went up to a little under the 40 line. this morning i started it and it was at a little over 40. and never dipped below all the way to work. it does fluctuate as i accelerate.


    any ideas whats going on?

    .,=======o00o<br />//__|__l__,\___\,___<br />l_---\__|__|---&#91;]lllllll&#91;] _<br />(o)_)____(o)_)--o-)_)__

    put a manual oil gauge on it and see a lot of the time its just the oil pressure sensor that goes bad. but you just wanna make sure.

    my pressure sensor died after 6 years/70k miles. I'd start looking there. :)

    Jerry / Whatevah

    2020 Gladiator Mojave - 33" Falken mud tires, LoD side steps, Zroadz bed rack, Quadratec QRC winch bumper, Superwinch EPi 9.0, Kleinn on-board air, Kleinn air horns, lots of lights, Yaesu ham radio with GPS tracker.

    Gone- 2012 JK Rubicon with stuff. Long gone- Long-arm 2001 Cherokee with stuff.

    i just changed oil and filter 4500 miles ago.


    i will check the sensor. i don't think it was ever changed.


    but what should it run at?

    .,=======o00o<br />//__|__l__,\___\,___<br />l_---\__|__|---&#91;]lllllll&#91;] _<br />(o)_)____(o)_)--o-)_)__

    it depends on the condition of the motor and oil viscosity. With light oil, 20-40 sounds ok. Mine runs a little higher after it warms up.

    Jerry / Whatevah

    2020 Gladiator Mojave - 33" Falken mud tires, LoD side steps, Zroadz bed rack, Quadratec QRC winch bumper, Superwinch EPi 9.0, Kleinn on-board air, Kleinn air horns, lots of lights, Yaesu ham radio with GPS tracker.

    Gone- 2012 JK Rubicon with stuff. Long gone- Long-arm 2001 Cherokee with stuff.

    Pressure should drop at idle. Mine runs 50 to 60 psi at highway speeds and 15 to 20 at idle; typical for an older 258. Check your oil level as well. Low oil level will make a low reading.

    Member since 2000

    Jeeps Owned'79 CJ5:

    Specs-

    - 258 I6

    - '93 Cherokee fuel injection and HO head,

    - bored 30 over

    - with 4x4 cam

    T18 tranny with granny low / Dana 18 t-case

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    Quote from whatevah


    it depends on the condition of the motor and oil viscosity. With light oil, 20-40 sounds ok. Mine runs a little higher after it warms up.


    I have 5W-30 in it cause i go up to NH to ice climb and it gets well below 0. its amazing how stiff the shifter gets when its that cold. i can just imagine the oil looks like molasses till it warms up. I'm changing the weight next oil change for warmer weather


    where is the oil pressure sensor. i did not get a chance to look for it last night?

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    Left side of the engine block. Pointing to the rear if the jeep above/forward of the filter. You'll need a large crescent wrench or channel pliers to remove it.

    Jerry / Whatevah

    2020 Gladiator Mojave - 33" Falken mud tires, LoD side steps, Zroadz bed rack, Quadratec QRC winch bumper, Superwinch EPi 9.0, Kleinn on-board air, Kleinn air horns, lots of lights, Yaesu ham radio with GPS tracker.

    Gone- 2012 JK Rubicon with stuff. Long gone- Long-arm 2001 Cherokee with stuff.

    Purolator or pure one. they have them at pep boys.if your wondering if i have fram i was told they are no good that they collapse.


    when i unscrew the sensor will oil come out? should i do this during an oil change?

    .,=======o00o<br />//__|__l__,\___\,___<br />l_---\__|__|---&#91;]lllllll&#91;] _<br />(o)_)____(o)_)--o-)_)__

    if the engine has been off for a few minutes and the oil is at the proper levels, you should be fine. I changed mine in front of a buddies house in a couple minutes.

    Jerry / Whatevah

    2020 Gladiator Mojave - 33" Falken mud tires, LoD side steps, Zroadz bed rack, Quadratec QRC winch bumper, Superwinch EPi 9.0, Kleinn on-board air, Kleinn air horns, lots of lights, Yaesu ham radio with GPS tracker.

    Gone- 2012 JK Rubicon with stuff. Long gone- Long-arm 2001 Cherokee with stuff.

    does the sensor have to be tightened all the way down to the "nut"? i tightened it till there was about a 1/4" to the block.


    thanks guys for the help. its a little unnerving to see the oil pressure drop down to 0. but now when hot it idles at 20 and cruses on the highway at 45-50.


    so what happens when there is no oil pressure does the engine run hotter because it has no lube? would you notice any other sign of lack of oil?

    .,=======o00o<br />//__|__l__,\___\,___<br />l_---\__|__|---&#91;]lllllll&#91;] _<br />(o)_)____(o)_)--o-)_)__

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