Low oil pressure warning after oil change.

[Vtur]

Sounds like some sort of intermittent internal pressure leakage. Pull the filter and inspect the output port oring. Any leakage through that oring will drops the pressure within the oil housing as the oil isn't pressurized enough in the housing to filtered through the filter media. Orings do shrink and expand when cold and hot hence it usually happens when first startups

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[Wolf Island Diver]

I checked the dipstick cold this morning. I really hate that goddamned thing. There’s no oil on the hash marks. But I checked the oil the week I first bought it and there was nothing on the stupid hash marks. There’s oil all over the top and bottom and sides of the tip which I presume is from the sides of the tube. That would normally indicate at least 1 qt low, but it’s never not read this exact way. I’ve never seen oil on the hash marks.

It makes little sense for it to be low since the engine hasn’t been burning oil and it’s well broken in. I’m really reluctant to add oil. There’s no sign of oil leaks and the bottom of the filter cup is clean.

The engine started up, rattled a bit with temporary starved lifters and jumped to around 40psi. I actually watched the numbers climb in real time from 0 on up to 40 in a few seconds. Then it settled down to about 27psi while it warmed up. Purring like a fat orange tabby. After warm up, it settled in at 21 PSI.

No codes, no dash warnings and ScanGauge shows no DTCs.

 

[PuddleJumper]

Self changed oil on 2021 eco. New oil filter is OEM and correct PN. Filled with 9 qrts Pennzoil Platinum Euro 5W50 MS 12991. No issues for first 60 miles. Then after a start got the low oil pressure light and oil gauge turned red. Oil pressure reading appeared normal range never dipping below 19psi. Then saw it dip to 6psi for just a second at idle. Shut engine down and called dealer. Dealer said to drive it over as there is a recall for this indication. On start up and drive over no issue. Tech was able to duplicate and scan showed low oil pressure code. Dealer flashes ECU and said was good to go. After another 50 miles low oil pressure again. Dealer made appointment and advised me to go ahead and drive it for the two weeks till my appointment. Stay tuned will advise if it seizes up before appointment. Dealer is taking responsibility if any damage occurs until appointment.
Anyone else experienced this?

I'd have it towed. I wouldn't risk it, on the solid chance its actually a low psi environment in their right now.

 

[Wolf Island Diver]

After another 50 miles low oil pressure again

Was this at startup or while driving? I want to differentiate that my warnings only occur at startup, and the gauge shows good pressure. The condition always corrects itself upon restart. I’m never seeing low pressure, unless you count the few seconds when the cold engine has just started, which I don’t. Also, I would expect all sorts of valve train noise in a true low oil volume/pressure situation beyond the brief 2 second rattle I hear on startup. I’m never seeing a loss of pressure or a new warning when driving. I’m convinced I missed the warning on startup the other day and that it didn’t happen while driving.

The time that the dealership “improperly” installed or torqued the oil filter, the warning came on while driving and would not go away on restart. I’m not saying the root of my current problem isn’t still the filter, just that the symptoms were different.

I still say that in a lot of these cases, this is either a faulty sensor (problematic unreliable product, as in the aforementioned GM case), failing sensors (these things happen), and/or overly sensitive ECU settings or shitty programming for transient low pressure conditions. I’m not sold on oil filter actually being a root cause outside of one not being seated or actually compromised in some way. I just don’t buy the oil sending unit being able to differentiate or care whether your oil filter is torqued to 25NM or 20NM or 30NM if it’s seated all the way and undamaged. Those conditions probably do account for some of these problems. The filters appear to be shit. But none of the techs I’ve talked to believe that filter torque is the issue and I’ve talked to several that have never torqued one.

 

[Vtur]

Was this at startup or while driving? I want to differentiate that my warnings only occur at startup, and the gauge shows good pressure. The condition always corrects itself upon restart. I’m never seeing low pressure, unless you count the few seconds when the cold engine has just started, which I don’t. Also, I would expect all sorts of valve train noise in a true low oil volume/pressure situation beyond the brief 2 second rattle I hear on startup. I’m never seeing a loss of pressure or a new warning when driving. I’m convinced I missed the warning on startup the other day and that it didn’t happen while driving.

The time that the dealership “improperly” installed or torqued the oil filter, the warning came on while driving and would not go away on restart. I’m not saying the root of my current problem isn’t still the filter, just that the symptoms were different.

I still say that in a lot of these cases, this is either a faulty sensor (problematic unreliable product, as in the aforementioned GM case), failing sensors (these things happen), and/or overly sensitive ECU settings or shitty programming for transient low pressure conditions. I’m not sold on oil filter actually being a root cause outside of one not being seated or actually compromised in some way. I just don’t buy the oil sending unit being able to differentiate or care whether your oil filter is torqued to 25NM or 20NM or 30NM if it’s seated all the way and undamaged. Those conditions probably do account for some of these problems. The filters appear to be shit. But none of the techs I’ve talked to believe that filter torque is the issue and I’ve talked to several that have never torqued one.

Probably your anti drain back valve is bad. It's unable to hold the oil in the filter housing overnight. Mine never sounds like dry starting when cold or warmed up.

In terms of the dipstick, i scrubed mine down with red scotch pad to a matte finish and it really helps.

Filter torque shouldn't be an issue as long it's bottomed out with the housing lip. The cap oring seal the housing and the smaller output port oring keeps the housing pressurized.

 

[Wolf Island Diver]

Probably your anti drain back valve is bad. It's unable to hold the oil in the filter housing overnight. Mine never sounds like dry starting when cold or warmed up.

In terms of the dipstick, i scrubed mine down with red scotch pad to a matte finish and it really helps.

Filter torque shouldn't be an issue as long it's bottomed out with the housing lip. The cap oring seal the housing and the smaller output port oring keeps the housing pressurized.

I’ll try that about the dipstick. Thanks for the tip. I still think this is electronic. Of the two recent back to back days it gave me the warning, one of them was after sitting for only a few hours in 100° heat outside of a basketball game. The engine was still warmish. I’ve started it first thing in the morning for the last two days and got no warning. I don’t think these cartridge filters have an anti drain back valve. Does the truck internally? I can’t find mention of it anywhere. I wish I had a factory service manual. This is one of the only vehicles I’ve owed that I didn’t have one and can’t seem to find one.

 

[Vtur]

I’ll try that about the dipstick. Thanks for the tip. I still think this is electronic. Of the two recent back to back days it gave me the warning, one of them was after sitting for only a few hours in 100° heat outside of a basketball game. The engine was still warmish. I’ve started it first thing in the morning for the last two days and got no warning. I don’t think these cartridge filters have an anti drain back valve. Does the truck internally? I can’t find mention of it anywhere. I wish I had a factory service manual. This is one of the only vehicles I’ve owed that I didn’t have one and can’t seem to find one.

Yes, unlike spin on filters. The valve is built into the housing. There's a sticky on the housing.

 

[Wolf Island Diver]

I haven’t had the issue since that last cluster of them. I haven’t done anything. I’ve got the supplies assembled to change the oil but I’m going to wait until later in the summer.

One thing to note about when all of this started. Around Farthers Day weekend, the trucks sat for probably 5 days. I had left the bed lights on and mostly drained my house battery. I’ve seen a few occasions where my Renogy seems to ignore its smart alternator switching and pulls from the starting battery. Usually this is because I’m plugged into a tender, so technically the Renogy is working normally in those cases because the voltage is up over 14 or whatever the cutoff is. I noticed it was on without being plugged in to the tender. Upon starting the truck it gave me the Aux Switches Unavailable message indicating the main battery had been depleted.

Now, I don’t know if the Renogy did this or if I have a main battery issue again. I’ve never heard of a bad(ish) battery showing excessively high voltage but I’m not an expert on battery failure modalities. The Renogy will actually charge the starting battery off of solar if the Lithium is fully charged.

So I had a case of the low pressure after the truck sat for weeks and another cluster of cases after this low battery issue. The Renogy and the main battery are fine now. I’ve got a solar panel that keeps the Renogy topped off. This could be totally unrelated. However when the trucks batteries died previously, they had to reflash the ECU it caused so many issues. I’ve never seen a vehicle go totally nuts like this truck did. I’m not sure the truck would have been drivable if I had immediately just replaced the starting battery.

I’m now curious if part of the issue is electrical (power to the ecu and sensors), which is different from ecu programming.

 

[Wolf Island Diver]

Did another oil change today. This is my final attempt to eliminate the random intermittent low oil pressure warning before I replace the oil sending unit and then attempt to get the oil filter housing warrantied.

I noticed the following:

1. I takes forever for the oil to drain out. Maybe I’m being ultra sensitive because I’m now expecting issues. But it continued to drip steadily for over an hour. Yes, the filter was out the fill cap was off. I don’t remember this the last time I changed the oil.
2. This plastic doohickey. It’s spring loaded and pushes in presumably when you screw in the filter. Mine is gritty and flimsy feeling. I’m curious if this is part of the issue. I do know, that the only parts you can buy are the sensor/sending unit, filter and the whole large filter cup assembly. I’ve been told that it’s covered under the power train warranty
   
   
   
   
   
3. When you torque to 25NM, the ridge in the cap is perfectly aligned with the ridge in the cup as others have observed. However, I went a little farther after the torque wrench clicked and there’s a definitive stop about another 3 degrees past that point. I wonder if this is the issue, stopping at the specified torque setting is still not fully seated even though the ridges line up.
   
   
4. Upon startup, I had a low pressure warning. I let it warm up, stopped it, started again and the warning was gone. I observed the same behavior last time I changed the oil, and then didn’t have another warning for several months until the intermittent problem started.

Bonus:

The fuel filter skid plate is a joke. Not only because there’s videos of folks destroying it in the rocks, but the design is crap. The three tiny 10mm bolts that hold it in place penetrate another bracket. I don’t remember my bolts being tight when installing before but I now see that the plates don’t line up so the bolts bind. I don’t know if this is from impacting the skid plate or from the factory but the misaligned bolt holes and threads mean that you can damage the threads screwing these in and more importantly the bolts are under lateral tension. One of mine broke under just more than hand tight. I had to extract the remaining piece. I don’t feel comfortable tightening the remaining bolts beyond snug. I can see how any real impact could easily sheer these bolts off. This skid plate isn’t sufficient and I wouldn’t recommend anyone play in the rocks without replacing it preferably with a skid plate that doesn’t only reuse these bolt holes. I’m going to switch to a full belly skid sometime next spring.

 

[Rusty PW]

When I change the oil filter. It never drains down. What's in there. I have to suck out.

 

[Wolf Island Diver]

When I change the oil filter. It never drains down. What's in there. I have to suck out.

Yeah, I sop that up with a rag but I’m taking about the steady, slow and never ending drip from the oil pan drain. I may be misremembering the previous oil change but I don’t remember it slowly draining out for this long. It was still dripping when I put the plug back in. Most oil changes in my experience are maybe 10-15 minutes before the dripping stops. I’m not saying this is indicative of anything, just a weird observation, although there’s supposedly an anti drain back valve in the filter housing assembly which could be the root cause of my oil pressure issue if that’s failing or sticking, etc.

 

[Sweetums]

25 Nm is too much torque, I don't care what the manual says. I went to 25 at my first oil change and had low pressure warnings about every other time I started the truck. Now I go to hand-tight plus 1/8 to 1/4 turn and have had no issues with low pressure warnings and I've had no leaks from the filter. Drive the truck for a couple of heat cycles and double check the filter is still snug, then you're good to go.

 

[Wolf Island Diver]

25 Nm is too much torque, I don't care what the manual says. I went to 25 at my first oil change and had low pressure warnings about every other time I started the truck. Now I go to hand-tight plus 1/8 to 1/4 turn and have had no issues with low pressure warnings and I've had no leaks from the filter. Drive the truck for a couple of heat cycles and double check the filter is still snug, then you're good to go.

Except, when my dealer did the last of my Wave oil changes, he did exactly what you did. Hand tight and then about 1/4 turn. My truck started throwing a low oil warning about 30 minutes down the road and it wouldn’t go off with restarts. It was towed back an hour later. All the tech did was tighten the oil filter with a wrench a good amount (I watched him) and start the truck. I never had the warning again until I did my own oil change and only 2 months later and only intermittently.

I don’t think the 25NM means anything. I think tight until it’s seated and snug. I noticed today that was at about 25NM on my torque wrench and then about 5 degrees. When I last changed it I went until it hit 25NM and no further. I didn’t inspect it closely, which I should have. I noticed what others have, the ridges lined up. Today I was about 5 degrees past that point. Those ridges line up dead on at 25NM with 2 different oil filters. I had issues last time. This time I tightened it a bit more. It didn’t feel too tight with my regular drive. It felt good. 18.4 ft/lbs is a tiny amount of torque. I think sometimes the filters properly seats with minimal hand tight force, sometimes with a wrench and something near the printed value. The variability could be the filters or the condition of the threads in the housing. I wouldn’t be surprised at all that an engineer worked backwards from what techs most frequently tightened the filters to to get them seated during pre-production engines. I suspect the low oil warnings are from a range of issues, from badly seated filters to computer issues. I have seen vehicles have this exact issue because of bad oil sending units. GM had this exact problem 10 years or more ago due to the sensors being crap.

I’m going to see what this thing does over the next few weeks and see if I have issues. I’ll try backing off and seeing what that does too. I’ve done a lot of oil changes in my life and always with a metal filter, hand tight and l’ve never seen this issue on any car I’ve encountered. I’ve never torqued a filter until this truck. My only concern regarding oil changes was up until this vehicle, the brand and spec of the oil and the interval. It’s kinda ridiculous.

 

[Sweetums]

I'm sure there's a relationship between the sensors and the software - my theory is that the computer is looking at a variety of sensors and if one doesn't show enough pressure x-miliseconds after startup, it throws a code. One of the factors that affects this is overtorquing the oil filter, but I'm sure there are others. For me, the main factor was filter torque and I haven't had any issues since abandoning the 25 Nm - but that's my truck in my conditions.

It's incredibly annoying. I'm still getting use to a vehicle this computerized and I'm having very mixed feelings. I love all the features, but part of me wants a CJ with a good old fashioned oil pressure gauge stuck to the dash.

 

[Butch-R-Vols]

Hi All;
I too changed my oil, filter and fuel filter. After about a 20 min. drive, I started the jeep back up and the Low Pressure Lights up the dash. Checked everything, and nothing seemed outta place. Finally took the Jeep to the dealer, everything checked ok and it was determined to be a glitch in a sensor or computer program. Dealer said they needed to flash the computer, cost was $191.88, which I balked at, to no avail. Drove the Jeep home, everything fine. Next day, started the jeep, drove to store, came back started the jeep and the LP warning lights up the dash. Now they tell me it could be the oil pressure sensor. Funny how this shows up after you change your own oil AND after its out of the 3 year, 36,000 mile warranty. Why should we have to pay for a flash of the computer when its their glitch that causes the problem!

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