resharp001

***TLDR - try changing to 5W30***

Cliff notes backstory. Around Oct ’20 my 3.6L I broke into the passenger side head to replace rockers/lifters to remedy good ole 3.6L tick. Since that day I have battled P0369. It’s been a long 4 years. It wasn’t too bad at the start, I’d occasionally get it, only when towing my camping trailer, and typically on long trips. Over the years it got progressively worse culminating in an awful ride home from a camping trip in April ’23. A 3hr trip took me about 20 times of stopping, resetting the code, and cycling the ignition. Mind you, this really sucks when you have a pig with 37s, towing a trailer, and you essentially lose all ability to maintain any sort of speed on the interstate and have to bail off to the side of the road quickly in some sort of safe manner. This eventually led to getting a few timing codes in the following months. The jeep sat for the summer of ’23 and in the Fall of ’23 I rebuilt the timing. Timing was indeed off a few links. I was 100% sure this was going to solve my P0369 cam code as well. I drove the heck out of the Jeep and had a few thousand miles on it, even a few short trips of towing a trailer under load. All good…..Bingo Bango! So, March ’24 I load up for a trip to Big Bend NP to go see the stars and I’m 3hrs into that journey when all the sudden….”ding”, CES, and effing P0369 code. I threw the code 3 times on the 8hr drive to my destination. The return trip home was miserable. 8 hours of stopping, resetting, cycling the ignition and seeing how far could get down the road till the next one.

SOOOo, here I am, finally making a thread about this, 3.5 years in the making. I’m starting this thread cuz if any of you have gone down the P0369, or other related cam code, you know 99.5% of what you read is a complete dead-end….brick wall….do not proceed. Nobody follows up, dealerships are a waste of time, and a lot of people are SOL after firing the parts cannon. Even the dealers fire the parts cannon, and when they can’t figure it out after running out of parts, they say “you need a new engine”.

Well, I’ve done a pretty deep dive down about every CDJR forum post and various videos regarding these codes. One thing I am pretty sure of is that 99% of the time this code is thrown, it IS NOT A BAD CPS!!! Good lord there are videos ad nauseam of people showing how to replace a CPS, and threads galore of “I’m on my 4th CPS now!” Folks, stop thinking it’s a bad CPS sensor! Having said that, there are videos that will show you how to test your CPS if you REALLY think that’s it.

Going to list some legit reasons for these codes in my opinion after going through all of this:

1. Bad wiring or harness to CPS – There is very little slack in the wiring to these cam sensors. There is a TSB out there for this and it’s a legit thing for some people. There are videos out there showing how to test the voltage to the wiring harness and the ground. The ground to these harnesses is shared with other components, so unless you are getting all sorts of codes on different things as well it is not likely a bad ground. I have seen people swear replacing the harness fixed their issue but I feel that is more common for a “circuit” code more than it is for an “intermittent” code like the P0369 and corresponding codes for Bank2 intake/exhaust and Bank1 exhaust (can’t recall those numbers specifically)
2. A tone ring on the cam that “walked” - I have no clue how these pressed on tone rings can walk out of alignment, but there are a good handful of videos out there with this exact thing. Mopar actually created a little tool used to verify the tone ring on the cam is in the proper position. It’s a few hundred bucks, is hard to come by, and is not very realistic for a DIY owner to pick up. If a tone ring walks, you’re going to get a cam code pop up immediately, and it’s going to be a persistent thing, not randomly sporadic like I experience. There are several videos out there showing how to read the signals from the CPS harness with an oscilloscope, another tool most of us don’t have. If the code is immediate and persistent though, and everything else has been eliminated, this is something to really think about if it’s been any sort of possibility at all.
3. Bad cam phaser – this is certainly a legit issue, but I don’t believe they are as big of a wear issue as a lot of these YouTube mechanics want to lead you to believe they are. There are videos out there showing you how to easily check if the phaser is bad simply by putting a wrench on the cam itself and observing any play. The cam and the phaser should be locked together so you should not be able to move that cam independently of the phaser….even a little bit. Motor City Mechanic on YT has a video showing this movement and also disassembling one of these phasers so you can see what is in there and how it works…..it ain’t too much. The bad part….you obviously have to remove the VC to test this.
4. Bad oil control valves or actuators. This just doesn’t seem like something big to me. I can’t see much going wrong with the oil control valve that is a simple bolt holding the phaser to the cam, and providing oil to the phaser. Maybe you could get debris in there, but if you got debris clogging this path you got bigger issues going on!!! Same thing with the actuator. Simple electrical connection forces a pin out to activate or deactivate the oil flow in the control valve. I can’t picture these failing often at all.
5. Oil galley bolts – This is a legit thing and a lot of people find it to be an issue. There is a TSB on it. In my opinion, this is going to be a bit more relevant to check if you’re throwing the code on hard downshifts. The VVT system is sensitive to oil pressure and if those oil galley bolts are not tight, you’re losing a little pressure there…..and that is going to be most notable with the code being thrown on downshifts. Should be pretty obvious in troubleshooting to know if that is typically when it’s being thrown.
6. Low oil – believe it or not, there are folks out there driving around with low oil levels, and this VVT system is SOOO sensitive to oil pressure. I think people just figure if there ain’t oil leaking out of their engine, there’s no reason oil level would be low. After all, the guy at the quicky station filled it up to what it should have been filled to. I have a catch can installed and I’m always amazed how much oil is caught in that. That is oil that is being shoved down to be combusted and NOT returned to the sump! I can see how people can chew through a little oil, forget to do their changes on time and regularly, and boom, low oil without even realizing it.

To expand a bit further, here is the list of everything that could be causing P0369 (and related codes) per the service manual:

resharp001

So, all this leads me to something that you won’t find easily. You certainly won’t see your dealers coming to this conclusion…..not even after they’ve replaced your phasers, cam, oil control valves, freagin’ whole heads, PCM, sensor, wiring……et al. Folks, I’m starting to think it’s often just that this 5W20 oil is too damn thin. Change to 5W30.

I have a trip to Moab coming up in early May. I’m up against the clock of figuring this out or facing a miserable 15hr drive (1-way) and then back. I had previously replaced my CPS wiring harness with new pigtail (didn’t change anything). The voltage to the harness and the ground to the harness are good. I do not believe I have a tone ring issue cuz my code is random and sporadic. My timing is good, I believe my cams to be fine. I would start to question my intake cam phaser next but I am not thrilled to just willy nilly break into this again on a lark…..just yet. One thing that is apparent to me is that my code issues on longer trips tend to get worse as the hours roll on. This leads me to think this is an oil problem after all with cam phaser next in line. I changed to 5W30 and a new filter. I logged 200+ miles on a stretch of road that I had just thrown the code on twice (without towing) in the previous day, once on its own and a 2nd time I forced it to catch it on my live data…which led me OFF of the path of thinking it could be electrical. I could see in the live frame-by-frame data that when the code was triggered, there was not an actual loss of signal between the CPS and tone ring. What I did observe is there was a variance between the camshaft desired position and actual position, I guess large enough to throw the code. That was very helpful to see.

Two weekends ago I logged 200 miles of driving with no code. I then hooked up the trailer and just drove on the interstate, with cruise control, under load and with stiff headwinds. I logged another 300 miles. No codes. This weekend I took a 6-hour, 400 mile, straight-shot joy ride (no trailer but stiff headwind) with the sole purpose of trying to flag this code again. Nothing. It’s kinda frustrating trying to FORCE a code and not being able to. I don’t feel there is a whole lot more I can do. I’m resolved at this point to say my trip to Moab will be the next real test. One thing I can promise is that I will follow up. If I start throwing the code again then I think my next course of action will be to replace the intake cam phaser. I hope I don’t have to break into this thing again though.

Could it be as simple as oil viscosity?? Let’s hope so. I did find one YT video of a guy who replaced his phaser while changing to 5W30 at the same time and it resolved his longstanding issue, and I found 1 thread online of two guys going back and forth about 5W30 with one of them providing longer-term updates of still being trouble-free. I’m hoping I can report the same! Time will tell, but I’m in this JK for life so I plan to hang around the forum for a good while still. Hopefully this thread can help someone along the way.

Shout @Jay2013jk. To be honest, it was one of your non-related oil comments that was the final push for me to try 5W30, even after having run across other sources leading me in that direction.

13JKUR

I am new to Jeeps and new to the thread. I have a 2013 And have the exact same issue with the p0369 code. Looking forward to see how the trip went. I’m going to do an oil change tomorrow to 5w-30 with a quart of Lucas. Mine has 162k miles.

13JKUR

After the oil change I drove on the same route to work that would always throw the code as soon as I hit the hill climb. I did not get the code but definitely felt that I could have made it throw the code if I wanted. It did get sluggish at times and then felt a “sudden burst” of power. Seems like it may be phaser issues. It acts like the vvt may be slow to respond. I just got the JScan so I’ll be doing the phaser cleaning today to see if that helps out any.

resharp001

As a followup, I've made the 1,000 mile journey to Moab and didn't throw the code. That follows ~1200-1500 miles back at home since changing to 5W-30 that I didn't throw the code. In a few more days I'll make the 1,000 drive back home, but I am highly confident thicker oil weight has been my solution.

If 5W30 doesn't solve your issue @13JKUR , I'd start suspecting the phaser next, but I would test the wiring harness cuz that is a lot easier than opening up the VC.

13JKUR

I will check the wiring first. I just got the JScan and did the cam phaser cleaning. Everything went through the cycle successfully. When I did the intake phaser 1 the rpm fluctuated a little. When I did intake phase 2 I got no change in rpm. I’m wondering if that means phaser 1 is bad or if phaser 2 is bad. I would expect both intake phasers to either both have a change in rpm or both not have any changes.

resharp001

I've not used that function on jscan yet. I'd be happy to do that procession on mine when I get home this weekend and see if I have similar results.

resharp001

I've got a full 2k mile round-trip to Moab completed with no codes! that follows the previous 1300 or whatever I drove trying everything i could to trigger that code. I'll try to do the phaser cleaning procedure tomorrow if I can remember and report back.

13JKUR

I haven’t gotten the code either but I still feel if I tried I probably can. I checked the voltage to the cam position sensor and it was at 5volts. Checked all cam phaser actuators they all looked good. My jeep is on 37s with stick 3.73 gears, programmed with JScan for new tire size, I feel when the rpm’s get low during cruise, instead of down shifting to accelerate it stays in the same gear causing it to lug the motor. I’m wondering if regearing to say 4.56 would help it out. As I write this I doubt it would actually work because when I shift it manually it still has the lugging feeling. It feels as if the vvt is lagging. I don’t know.

resharp001

Oh man, 3.73 with 37s sounds......miserable. When I first went to 37s I had 4.10 gearing. I went maybe 9-10 months like that before it wore me down. It was the top end that did it to me. I couldn't stand essentially losing 5th gear on the highway and having to downshift to 3rd if I had to pass or there was even a slight headwind.

Did you watch that video by motor city mechanic where he disassembles a phaser? There isn't much going on inside one of those to fail. I tore one apart myself. There is literally just a little spring and lock pin in those that the oil pressure is moving back and forth. Outside of some very random particle jamming that, or I guess the little plastic cap in there breaking, I think those failing is a lot less than people want to believe.

I just went out and performed that cleaning function on mine to compare results. RPMs surged a bit while cleaning intake phaser 1, they did nothing while cleaning intake phaser 2. These are the same results you saw, and I have no reason to believe my intake phaser on bank 2 has a problem. I can't explain why there is no rpm increase when cleaning intake on bank 2. I would think it would be the same as well but for some reason it is not.

I'm running a ~120 tire/wheel combo (37s on ATX beadlocks) with 4.88 gearing and have a heavy ass full float PR60 rear axle too. My Jeep is sure not a light thing, so I can relate to the engine being under a lot of load even when I'm not towing my camping trailer which adds another ~3k lbs loaded down. I used to only throw the code when I was towing but it got worse over time to when I'd throw it just driving the jeep on long road trips. I really think if it's not throwing the code on you even when you feel like it could, that is a good sign. I personally wouldn't do anything else until it starts throwing the code again. Regearing would certainly improve your driving experience, though your wallet would be lighter. TBH, it would make a big difference and really help both the engine and the transmission out, but I can see not wanting to put that money into it when you think there could be engine aggravations you still need to work out. My confidence level is running pretty high that my issues may finally be behind me.


Also, my impression of the phaser "cleaning" process is more that it's flushing oil through the oil control valve. There is not much space for oil to travel in the phaser itself and there's no direct path through that....it's essentially a dead end at the spring pin in there so the cleaning is more of the oil control valve passage way (the big bolt holding the phaser to the cam).