Oil pressure drops as jeep warms up
01-14-2011, 06:26 PM
#31
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Year: 89
Model: Cherokee
Engine: Inline 6
thats why im on the forum, i never use this but the nois is driving me crazy, dont like driving it when its rattling or when the oil presure gets low, because when i drive it for like 40 miles, then stop at a light its sluggish like it barely wants to get moving again when the oil pressure is down to almost nothing. i know there is absolutly some kind of problem but i dont know exactly what it is, but im bouts to just got to work at it, change the pump the bearings everything this weekend i guess
01-14-2011, 08:32 PM
#32
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Year: 2000
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Factory oil pressure gauges are notorious for being less than accurate. Get a real oil pressure gauge on it and check. It you oil pressure were that low you should feel the engine running rough not just hear it. It could just be a bad sensor.
01-15-2011, 01:20 AM
#33
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nah man thats the thing tho, i can feel it runing funny, like its sluggish from a stop and its chopy when i acelerate from a stop, i can hear and feel the difference so i know the gage is right
01-15-2011, 01:23 AM
#34
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Year: 89
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Warmer it gets the lower the oil pressure
I have an 89 Cherokee with a 4.0 inline 6, when its cold ill start it up and the oil pressure will be where its supposed to be at 45 but as it warms up the oil pressure drops till it hits like 5 to 10 or even lower the farther I drive, when I give it gas it goes up to maybe 20 but when I come to a stop it idles around 5. the engine will rattle too, only when the oil pressure is down that low when its cold it sounds like a champ, or even when its warm and the oil pressure is low, and I step on the gas it wont rattle. what could the problem be?
01-15-2011, 01:26 AM
#35
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Year: 1996
Model: Cherokee
Engine: 4.0L HO
How many miles do you have? That seems like awfully low pressure, mine at idle when its cold is around 60-70 and driving at 80. Once it warms up its more like 40 idle and 60 while driving.
01-15-2011, 01:28 AM
#37
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01-15-2011, 01:31 AM
#38
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Year: 1996
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Looking through your other thread, this makes me seem like I'm the one with the problem. People saying low oil press is the norm?
01-15-2011, 01:36 AM
#39
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yeah i dont even think that right tho, like yeah you have extreemly high oil presure but its not supossed to drop down to ten ever. its bad haha all the machanics i talk to say that it should run 30 maybe 25 20 at the lowes at idal when its hot, so i don know
01-15-2011, 01:45 AM
#41
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Before you spend money on a pump drop the oil pan and check a couple of rod bearings. see how worn they are. If you get a new set of bearings plastiguage then to see what you clearances are. if it its rattling some that may by you some time. you got to drop the pan anyway. bearings arent that much. May save you from dropping the pan twice anyway.
01-15-2011, 02:00 AM
#42
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Originally Posted by jesse jay
I have an 89 Cherokee with a 4.0 inline 6, when its cold ill start it up and the oil pressure will be where its supposed to be at 45 but as it warms up the oil pressure drops till it hits like 5 to 10 or even lower the farther I drive, when I give it gas it goes up to maybe 20 but when I come to a stop it idles around 5. the engine will rattle too, only when the oil pressure is down that low when its cold it sounds like a champ, or even when its warm and the oil pressure is low, and I step on the gas it wont rattle. what could the problem be?
01-15-2011, 02:17 AM
#43
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Year: 1990
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I would look at your main crank bearings. If the motor has never been rebuilt then they could be worn out. I think the rattling is metal on metal contact being made, though not 100% on that. Are you burning oil out the exhaust at all?
01-15-2011, 02:44 AM
#44
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im thinkin replace the main crank bearings and the rod bearings and i got a new pump to put in it already.
01-15-2011, 02:46 AM
#45
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Year: 89
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