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Oil Pressure 0 at Idle and 20 while driving?

T

thanasi85

NAXJA Forum User
Location
Sacramento, CA
Its an 88 4.0L 190,000 miles, its been driven very little in the past year and I just bought it and started driving it for about a good 2 weeks, took it out wheeling a few times no issue but today just driving in traffic to and from work I noticed the oil pressure gauge was 0 at idle and 20 while driving and not sure where to start looking. It was the hottest weather today that I have driven it in almost 90 degrees so not sure if maybe the PO didn't put 10w-40 in which is what Ive always done in my other XJ and the warmer temp has caused the oil whatever weight it is to thin causing less oil pressure or if the pumps going out?
 
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cruiser54 said:
Test the oil pressure with a rented mechanical gauge to be sure.

What brand of oil filter are you using?

Any strange noises when the pressure drops?
Click to expand...

Ya was thinking of renting one at autozone next time I went. Oil filter in in now is a Fram double guard, much nicer than the cheap STP ones I always run and no noises I noticed while the gauge was at 0. An update to it is that the jeeps been sitting for an hour or so now in the shade and just started it up to run up to the store and it jumped right up to 20 and stayed there at idle and would raise up to a little above 20 while driving.
 
Could the oil weight the PO put in cause this if it was something less than 10w-40, he was a young kid and said he did an oil change a few weeks before I bought it but he also said the jeep had a v6 in it so not sure he was very mechanically inclined. I alway run 5 quarts 10w-40 and a quart of Lucus oil stabilizer and have always been golden
 
mine bounces around alot on the trails. when im going on a climb of some sort. it will drop to 0 then back up to 30-40 when driving on a regular road. is that normal sorry OP not trying to highjack
 
cruiser54 said:
JUNK.

Mopar, Wix or Napa Gold are excellent filters and easy to find.
Click to expand...

X2

Fram makes a terrible oil filter product. Read:

http://www.dslreports.com/forum/r21883344-Tech-Review-The-Long-Waited-FRAM-OIL-FILTER-REVIEW

I've been using Purolator filters on every engine build for the last 15 years. Zero issues reported.

OP - you've got some work ahead of you. First thing's first - I'd pull off your current oil filter, cut into it, and see if there are any metal fragments in the filter. If there are, that means that you probably have some bearing issues. Extremely low pressure at hot idle and marginally higher pressure with higher RPMs usually means bearing failure. It won't matter what oil or pump you're using if your bearings are out of clearance - your pressure will still read low.

Check the oil filter and get back to us.

Jim
 
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SeeingSpots said:
X2

Fram makes a terrible oil filter product. Read:

http://www.dslreports.com/forum/r21883344-Tech-Review-The-Long-Waited-FRAM-OIL-FILTER-REVIEW

I've been using Purolator filters on every engine build for the last 15 years. Zero issues reported.

OP - you've got some work ahead of you. First thing's first - I'd pull off your current oil filter, cut into it, and see if there are any metal fragments in the filter. If there are, that means that you probably have some bearing issues. Extremely low pressure at hot idle and marginally higher pressure with higher RPMs usually means bearing failure. It won't matter what oil or pump you're using if your bearings are out of clearance - your pressure will still read low.

Check the oil filter and get back to us.

Jim
Click to expand...
Not sure how to cut into the filter without getting metal fragments in it from the cutting its self?? Maybe I will just try and pull the filter inside out in pieces with something and see what I find. Also I started this morning and oil pressure right back up to 40 like normal but I only started it to pull in the driveway so idk what’s going on with it?
 
thanasi85 said:
Not sure how to cut into the filter without getting metal fragments in it from the cutting its self?? Maybe I will just try and pull the filter inside out in pieces with something and see what I find. Also I started this morning and oil pressure right back up to 40 like normal but I only started it to pull in the driveway so idk what’s going on with it?
Click to expand...

Change the filter and see what happens. That's good enough.
 
Drill a small hole and then use a pair of metal snips to cut away the body - it's just tin. That shouldn't produce any new fragments.

Presuure will always be a little higher when the oil is cold. Let it idle for a bit and keep an eye on your gauge. If it drops below 10psi, shut it down.
 
mine runs about 40 cold idle 55 cold @ speed, 45ish warm @ speed dropping to 25 @ idle. Running Rotella 5W40 synthetic and a CM filter (no bypass) when idle pressure drops below 20 hot I change the oil and filter, no problems so far

I would change the oil and filter and see what happens. I'm definitely in the Wix/NAPA Gold (same filter) camp as well, Purolator is good too, Champion is acceptable, Fram is traditionally crap, don't know if they've gotten any better over the years but when consistently good products are on the market for less money why take the chance?
 
I have seen multiple Fram filters cause this exact same issue. Ask PacEd. I had him throw away the Fram and presto his oil pressure was fine. That was several years ago and I think he is still driving that rig.
 
old_man said:
I have seen multiple Fram filters cause this exact same issue. Ask PacEd. I had him throw away the Fram and presto his oil pressure was fine. That was several years ago and I think he is still driving that rig.
Click to expand...

I don't doubt that at all. Seen it numerous times right here and on other Jeep forums.
 
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