Low Oil Pressure
#1
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Location: Manton Michigan! Blessing countryy!
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Model: Cherokee
Low Oil Pressure
1999 SPORT 80,000 Miles
5w30 Tried Mobil filter vs Fram-- same!
Put 3K miles on since i bought it, AVG 1500 per month.
Fresh oil and filter, since start of problems,
Dropping to 8 on Hot IDLE.
at 1600 only 23 PSI.-- Hot
No noticeable noise, and have replaced sender and used multiple gauges.
Never above 48 PSI at anytime cold. No matter what rpms.
Please help, ive parked it and i know the worse case and the least worse cases, im hoping just a bad relief valve, on the pump.
5w30 Tried Mobil filter vs Fram-- same!
Put 3K miles on since i bought it, AVG 1500 per month.
Fresh oil and filter, since start of problems,
Dropping to 8 on Hot IDLE.
at 1600 only 23 PSI.-- Hot
No noticeable noise, and have replaced sender and used multiple gauges.
Never above 48 PSI at anytime cold. No matter what rpms.
Please help, ive parked it and i know the worse case and the least worse cases, im hoping just a bad relief valve, on the pump.
#2
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Year: 1998
Model: Cherokee
Engine: I6 4.0
1999 SPORT 80,000 Miles
5w30 Tried Mobil filter vs Fram-- same!
Put 3K miles on since i bought it, AVG 1500 per month.
Fresh oil and filter, since start of problems,
Dropping to 8 on Hot IDLE.
at 1600 only 23 PSI.-- Hot
No noticeable noise, and have replaced sender and used multiple gauges.
Never above 48 PSI at anytime cold. No matter what rpms.
Please help, ive parked it and i know the worse case and the least worse cases, im hoping just a bad relief valve, on the pump.
5w30 Tried Mobil filter vs Fram-- same!
Put 3K miles on since i bought it, AVG 1500 per month.
Fresh oil and filter, since start of problems,
Dropping to 8 on Hot IDLE.
at 1600 only 23 PSI.-- Hot
No noticeable noise, and have replaced sender and used multiple gauges.
Never above 48 PSI at anytime cold. No matter what rpms.
Please help, ive parked it and i know the worse case and the least worse cases, im hoping just a bad relief valve, on the pump.
Any chance it could be the sending unit? Do you know anyone with a mechanical gauge that you could borrow?
#3
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Model: Cherokee
#4
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Year: 1997
Engine: 4.0
That's low but not crazy low.
I have a '97 with 202k miles...owned it since new. At hot idle, it will sit on the low side of 10 psi, probably about the 8 psi you are getting. By 1500 rpm, though, it stays right at 40 psi. About the most pressure I ever see at higher rpm is maybe 50 psi.
BTW, my figures are all with 10w40. Last summer, I started getting nervous at the low oil pressure at idle in hot weather, so I went from using 5w30 to 10w40.
FWIW, my Jeep did not and does not have any oil burn or lack of compression. I simply figured that I was loosing a bit of pressure due to the mileage and decided to go a little thicker.
I have a '97 with 202k miles...owned it since new. At hot idle, it will sit on the low side of 10 psi, probably about the 8 psi you are getting. By 1500 rpm, though, it stays right at 40 psi. About the most pressure I ever see at higher rpm is maybe 50 psi.
BTW, my figures are all with 10w40. Last summer, I started getting nervous at the low oil pressure at idle in hot weather, so I went from using 5w30 to 10w40.
FWIW, my Jeep did not and does not have any oil burn or lack of compression. I simply figured that I was loosing a bit of pressure due to the mileage and decided to go a little thicker.
#5
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Year: 1991
Model: Cherokee
Engine: I-6 4.0 HO
Searching will yield faster results. Many issues can cause (have been discussed about) low oil pressure:
https://www.cherokeeforum.com/f2/low...fusion-126237/
https://www.cherokeeforum.com/f2/low...ressure-96842/
https://www.cherokeeforum.com/f2/tim...l-pump-120119/
(my copy/paste finger is getting tired)
I'm really not trying to be a troll here, but searching will yield you many answers MUCH more quickly than sitting there refreshing the page as you wait for answers to a topic that has been discussed (and solved) countless times.
Common causes:
Worn out oil pump (200k seems to be the kill date often, but not always)
Worn bearings (mains contribute to most oil pressure)
Sludge at the sending unit hole
Fram filters (they suck and cause problems)
Faulty sending units (some new units out of box suck)
Problem with gauge itself
Filter/filter adapter leak
The list goes on...
https://www.cherokeeforum.com/f2/low...fusion-126237/
https://www.cherokeeforum.com/f2/low...ressure-96842/
https://www.cherokeeforum.com/f2/tim...l-pump-120119/
(my copy/paste finger is getting tired)
I'm really not trying to be a troll here, but searching will yield you many answers MUCH more quickly than sitting there refreshing the page as you wait for answers to a topic that has been discussed (and solved) countless times.
Common causes:
Worn out oil pump (200k seems to be the kill date often, but not always)
Worn bearings (mains contribute to most oil pressure)
Sludge at the sending unit hole
Fram filters (they suck and cause problems)
Faulty sending units (some new units out of box suck)
Problem with gauge itself
Filter/filter adapter leak
The list goes on...
#7
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Trending Topics
#9
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Year: 87
Model: Cherokee
Engine: 4.0
I'm not very knowledgeable on the issue so i would be no help but do NOT figure its just the gauge or sending unit. If i goes down to zero PULL OVER.
I have a buddy that blew the motor on his Ford Ranger because he did that exact thing. It went to 0 and he noticed no problems and he kept going and sure enough he blew the motor.
I have a buddy that blew the motor on his Ford Ranger because he did that exact thing. It went to 0 and he noticed no problems and he kept going and sure enough he blew the motor.
#10
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
#11
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Your check engine light is coming on?
The highest mines ever been is maybe 48. At hot idle it hangs around 15... Usually just sits around 40 or so. Never had an engine light come on. I thought it was normal for these things to be around 15 - 40 psi?
The highest mines ever been is maybe 48. At hot idle it hangs around 15... Usually just sits around 40 or so. Never had an engine light come on. I thought it was normal for these things to be around 15 - 40 psi?
#12
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
"I just dont like seeing my check gauges light come on."
#13
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Year: 98 2 Door SE
Model: Cherokee
Engine: 4.0 High Output
My 98 pretty much the same on low side hot at idle 10psi , hit the gas it climbs to about 40 & stays there under any load. Did sending unit , clean out of sending unit tube good filters 123K . No change . No noise . Never had check gauge light come on. Is idle rpm a bit low ?
#14
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Model: Cherokee
Alright so dropped the pan found no buildup at all, looked great, tore the pump off and took it apart, looked a little buildup around the oil suck up part but no blockage, pulled A rod bearing and will post a picture soon, i wonder if my pump has a bad pressure relief valve?