I have a 2000 wrangler with a 4.0. The oil pressure drops off to 0 at idle after driving about 1 hour. Cold seems fine, 45-55. I put anouther gage it matches the one in the dash, new oil pump. Still goes to 0 at idle. On interstate about 1800 rpm's warm carries about 20 lbs. Any help is appreciated thank you.
low oil pressure help please
- Thread starter nstrut
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LVRockCrawler
New member
in my experience (and i hope i'm wrong) - normal pres. when cold and low/no pres. at temp is a problem with the main bearing or cam bearing tolerance - could be an oil pump problem (even if its new)or even a clogged filter (not likely tho...) again - i hope i'm wrong - did it overheat really bad or run real low on oil lately? usually something like that would have to happen to damage the mains or cam brngs..... sorry, like i said, my experiences havent had happy endings... hopefully someone here will have better news for ya.... and welcome to Jeepz - you'll like it here!
g'luck and let us know what you find out!
g'luck and let us know what you find out!
Sparky-Watts
Banned
1st of all, Welcome to Jeepz! Hope you decide to stick around awhile, I'm sure you'll like it here.
Now, on to your question. You said you put another gauge on it, but how? Did you just wire up to the existing wires by disconnecting the old gauge? Or did you use a mechanical pressure gauge directly to the engine? If you just hooked up to the wires, that's not really a valid test, as it could be your sending unit that's bad. Jeeps tend to have a problem with sending units going bad. Hopefully, that's all it is, a quick $15-$20 fix. Let us know what you find. Whatever it is, I hope it's not fatal!
Now, on to your question. You said you put another gauge on it, but how? Did you just wire up to the existing wires by disconnecting the old gauge? Or did you use a mechanical pressure gauge directly to the engine? If you just hooked up to the wires, that's not really a valid test, as it could be your sending unit that's bad. Jeeps tend to have a problem with sending units going bad. Hopefully, that's all it is, a quick $15-$20 fix. Let us know what you find. Whatever it is, I hope it's not fatal!
LVRockCrawler
New member
good idea = hook up a MECHANICAL gauge and see what you get.... that may show better pressure!
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Sparky-Watts
Banned
Oh....
.....well, so much for my hopes that it would be something cheap and easy.....kinda like my ex.
currupt4130
VT Hokie
Little bitter today Sparky?
Sparky-Watts
Banned
Nah, you know me....I'm bitter every day! :lol:
This started about 50,000 miles. I keep oil changed every 3,000 miles. Other than that it doesn't use a drop in 3,000 miles. I just added another gauge with the one in the dash. It reads a little lower than the one in the dash. After an oil change it will go about 500-750 miles before it starts acting up. If you just change the filter when it starts acting up it will go about another 500 miles before starting again. I run Havoline 10w 30, I am going to try something different next change, maybe a 30 or 40 weight. thank you
slo-wrench44
New member
any progress with this??? i have the same problem with my yj . i have quite a few miles on mine and i have a mech gauge also. after one oil change it just dropped to nothing. it did run about 1 1/2 qts low for a short time about 10 miles but i dont know if that did it
No luck yet. I tried sae 30 weight, didn't help. Then changed to 20w-50 and that didn't help. Everyone is blaming cam bearings, I don't agree. It has 58,000 miles on it. I had the pan off and the mains and rod bearings looked new. The motor is clean as a pin. So I am still driving and looking for the answer. But here is the kicker, when I drive to work 41 miles about 1 hour and let it idle in the parking lot the pressure will drop to 0 but there is no noise. I think something should be rattleing or knocking, just don't make sense. Thank you
Sparky-Watts
Banned
You said the mains and rod bearings looked new, but did you actually get out a feeler gauge and check the tolerances? They could look perfectly fine but still be loose as a goose.
One other thing could be that there is a hunk of sludge or other foreign object in the motor somewhere. If it's sludge, it would almost make sense about it happening when warm. The sludge would congeal when the engine is cool, but once it is warm, it could loosen up the "oil loogey" and send it coursing through the engine, stopping up an oil passage. It could also just be a small speck of sludge or other object right at the passage to the sending unit that is blocking it off right there, giving a false reading.
These are just ideas and suggestions....I figure the more we throw out there, the more likely we are to come up with something that works to solve your problem. Nothing we hate more than a sick Jeep, whether it's ours or someone else's. Heck, I'd even send your Jeep a Get Well card if I thought it would help.
One other thing could be that there is a hunk of sludge or other foreign object in the motor somewhere. If it's sludge, it would almost make sense about it happening when warm. The sludge would congeal when the engine is cool, but once it is warm, it could loosen up the "oil loogey" and send it coursing through the engine, stopping up an oil passage. It could also just be a small speck of sludge or other object right at the passage to the sending unit that is blocking it off right there, giving a false reading.
These are just ideas and suggestions....I figure the more we throw out there, the more likely we are to come up with something that works to solve your problem. Nothing we hate more than a sick Jeep, whether it's ours or someone else's. Heck, I'd even send your Jeep a Get Well card if I thought it would help.
