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Oil preasure pegged at 80psi but runs fine?!?! Help!

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Old Feb 18, 2011 | 06:08 PM
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Year: 2000
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Exclamation Oil preasure pegged at 80psi but runs fine?!?! Help!

Today while driving my oil PSI went from normal while driving to 80 PSI! Pulled over, checked oil and was a little low so i added some and to my dismay the issues persists. The funny part is there are no oil leaks and a lack of ticks and knocks from under the hood. There were no noises orginally, but when the oil preasure is that high i figuered there would be. Could a bad oil preasure sending unit cause this? I picked one up on they way home with fluids and filter for a oil change, but it was too dark to try to work on the Jeep. Advice/help please
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Old Feb 18, 2011 | 06:11 PM
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My jeep is the exact same. And i have no idea what it is. so hopefully someone has a solution! i'd be happy to know, sorry i'm no help though.
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Old Feb 18, 2011 | 06:22 PM
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Could be, I've left mine unplugged after changing oil and it spikes out and doesn't move. The harness is right above the oil filter, good luck
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Old Feb 18, 2011 | 06:22 PM
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This is almost assuredly the oil pressure sending unit.

When they fail, they usually fail with abnormally high readings.

And this is a COMMON failure on the 4.0 engine.

Replacement should take care of this for you.

I have had mixed (poor) luck with certain aftermarket oil pressure sending units, so this is one item that I recommend purchasing from Jeep. But as you already have one, slap it on and see if it takes care of this. Smart money says it will..........
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Old Feb 18, 2011 | 06:50 PM
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Originally Posted by PatDig
Could be, I've left mine unplugged after changing oil and it spikes out and doesn't move. The harness is right above the oil filter, good luck
Mine isn't always spiked, just when the go pedal recives any pressure.

Originally Posted by tjwalker
This is almost assuredly the oil pressure sending unit.

When they fail, they usually fail with abnormally high readings.

And this is a COMMON failure on the 4.0 engine.

Replacement should take care of this for you.

I have had mixed (poor) luck with certain aftermarket oil pressure sending units, so this is one item that I recommend purchasing from Jeep. But as you already have one, slap it on and see if it takes care of this. Smart money says it will..........
Thanks, I hope it wokrs, i got mine at car quest. I hope I'm all good come tommo, I missed out on mudding cause I didn't know what was wrong.
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Old Feb 18, 2011 | 06:56 PM
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x2 on the oil pressure sending unit
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Old Feb 18, 2011 | 07:02 PM
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x3 on sending unit
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Old Feb 18, 2011 | 08:59 PM
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From: Colorado Rocky Mountains
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Engine: 4.0 I6
Default Yep, oil press. sending unit

Sounds exactly like what my 96 XJ did when the oil pressure sending unit went bad. I think it's like a 30 or 40 dollar part if I remember correctly, and just screws right on/off.
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Old Feb 18, 2011 | 09:50 PM
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I think it is more like $20-25 even
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Old Feb 18, 2011 | 10:32 PM
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If the oil pump fails it can do this. It did on mine. My pressure shot up to max and then it blew the oil filter off. I replaced the oil pump and the pressure is back to normal.
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Old Feb 19, 2011 | 12:10 AM
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at least it's not like mine... reads between 5 and 20 psi, NEVER any higher
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Old Feb 19, 2011 | 09:38 AM
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Well, im gonna replace the sending unit in a little, I'll let yall know if it worked.
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Old Feb 19, 2011 | 11:19 AM
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Luckily it was the oil preasure sending unit. I hope its the same problem for u dev daddy. Thanks for all the help yall!
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Old Feb 19, 2011 | 11:49 AM
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HI all. i am new the forum, I have a 94 jeep Grand Cherokee Lorado. Mine just started having issues, oil pressure normally runs even at 40psi- driving or at idle. but here recently it popped codes for O2 sensor, EGR valve, and Intake air temp sensor, now oil psi is 40 driving and 80 at idle...........As well having issues with heater showing and error (er) message on the temp display on occasion. And is anyone else having issues with a the comp showing "service 4wheel drive sensor" what dose this mean???
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Old Feb 19, 2011 | 06:21 PM
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Originally Posted by idaho_jeepgirl
HI all. i am new the forum, I have a 94 jeep Grand Cherokee Lorado. Mine just started having issues, oil pressure normally runs even at 40psi- driving or at idle. but here recently it popped codes for O2 sensor, EGR valve, and Intake air temp sensor, now oil psi is 40 driving and 80 at idle...........As well having issues with heater showing and error (er) message on the temp display on occasion. And is anyone else having issues with a the comp showing "service 4wheel drive sensor" what dose this mean???
Tip for you. You should start a new thread for your new problem. Much more efficient and you will get way more accurate responses than piggy backing onto this thread.

And always post the EXACT codes. With OBD, the devil is in the details.

Last edited by tjwalker; Feb 20, 2011 at 11:47 AM.
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