IIQII

OK, from my previous thread I had been troubleshooting and repairing multiple codes. Replacement of a couple cams and phasers cleared those DTC's.

Now after driving for a while a P0394 code is set followed shortly thereafter by a Torque Signal Denied resulting in limp mode. This is on Bank 2 position 2 intermittent signal. Again, it takes a while for the code to appear. If cleared it could take 3-5 drives for it to show up again. The drives are nothing strenuous. Pretty flat roads just driving to work. I have not seen it clear on parking over night.

During all the work previously both camshaft position sensors were replaced with Mopar parts (all cams, phasers, sensors are Mopar). The Jeep will function and drive great for a while before throwing the P0394 code. There's a lot of info out there on what it could be. Anything from bad wires, oil pressure, phasers and even tone (reluctor) wheels.

The oil I am going to rule out as the oil is relatively fresh (change when all the other repairs were started with very little driving). The oil galley bolts were removed, cleaned, loctite 243 applied and torqued during the previous repairs and were checked each time the valve covers were removed. That combined with oil pressure from data collection on my D8 shows the oil pressure is fine (standard and VVT oil pressure match).

Bank 2 has a new exhaust phaser, intake cam and intake phaser. The intake cam was switched after I determined the tone (reluctor) wheel had indeed shifted by about 70-80 degrees. I have seen 2 shifted wheels, both on the intake cams and the data and codes for this P0394 do not indicate anything with that would indicate a cam/reluctor issue. The positions were erratic giving a good indication there was something up. Now all cams match up pretty close.

Ruling out oil and cam (possibly phaser) I am going to start with verifying the VVT solenoid actuation/operation. If that checks out then a swap of the sensors side to side to see if it follows the sensor. If it does not follow the sensor then I will check the connectors/harness for voltage and ground and see if there is any loose or damaged wires by visual and with movement.

Some of this stuff can start to drive you nuts....

resharp001

so this is the same code that has been a pain in my ass cept on the Bank1 side (P0369 for me). I had dealt with this one for so long, and 98% of my issue was fixed by going to 5W30, and to be more specific, NOT a high mileage version. I could pretty much force this code at will with a short bit of driving, and after moving to 5W30 I tried everything in my power, logging so many miles in high wind, towing trailer, 6+ hrs stretches at a single time.....thousands of miles and so many hours, including a trip to Moab and another trip to Ouray, CO. In that time I did nothing but change that oil. I had an issue coming back home from Ouray in June, and it was due to low oil.....so i was not surprised by the code, but i was from the disappearing oil!

I can't recall what you are running right after your work. When you really go down the rabbit hole of this specific code across all CDJR vehicles, the finger so often starts getting pointed to the oil. My believe is that VVT is so sensitive, and it just takes a split second of a skip to throw this code....just that 1 second where the pin in the phaser isn't actuated as quickly as the computer wants it to be.....which then misplaced your camshaft for a moment and engine goes into self-preservation mode.

I feel your pain man, I feel your pain!! If you hadn't run across my thread it's here -

https://www.jk-forum.com/forums/stoc...g-saga-361310/

IIQII

Good call man, I am running a high mileage oil in it. I may just change it to give it a try.

I am getting tired of the light and limp with this thing. This one really kinda ticked me off. A day or 2 of running strong and BOOM, code... Only thing I am taking solace in is all the other work I have done and crap I have replaced is working and it got rid of those codes. Those tone wheels took a little diagnosing and time, but were interesting. Doing the timing set and then reopening the VC's for phasers and cams... either I have been lucky or my paranoid work habits have helped.

I will keep this thread updated with anything I find so that someone else may possibly get some help.

resharp001

I really can't put together a theory why additives in a high-mileage oil would matter, but when I think way back to when my issues started, I swear they coincided around the time I switched to high-mileage. I went from 5W20 high mileage to straight up 5W30, so I guess I can't say it was the oil viscosity rather than the non high mileage. I honest to god didn't think the oil change would make any difference, but like i said, i tried everything in my power to force that code again and the jeep just kept going and going.

IIQII

Here's a question, Bank 2 is driver side position 2 is the exhaust cam side of the sensor because the sensor locations go from left to right. Or am I mistaken?

resharp001

You are going to be Bank2 on the intake cam. this picture is from the service manual for the P0394 code -

IIQII

So that makes it more interesting. That is a new cam, phaser and OCV.

IIQII

OK resharp001, I have 5w-30 oil in the Jeep but it is the high mileage variant. 5w-30 is what is stated on the oil fill tube cap.

Mine is a '12 which explains the difference in the between what mine is saying is required and yours (I am assuming your rig is a '13+ and yes I know the joke on assuming).

One thing I have noticed is that the code is thrown when temps are warm. Down here the temps now can easily get to mid 90's with high humidity. The last couple days have been cooler with rain. For the last day and a half with the cooler temps (cloudy and rain) I have not seen the code or the traction control that follows it.

The heat here and your experience going up a weight grade on the hot side of oil has me thinking of maybe trying some 5w-40. The engine is high mileage so the higher viscosity at temp may help (there are no leaks, so no worries or gain needed there).

I am still going to look over and check the harness and swap the sensors again just to mark that off the list, but maybe the oil is the culprit and given the mileage it needs a higher weight. At least that is relatively quick and easy.

Poke holes in my theory.

resharp001

That is very interesting. I didn't realize that before '13 they simply stated 5W30, and then in 2013 they apparently started recommending 5W20, though the owner's manual still states that 5W30 is ok to use. Just dumb. I can only suspect trying to eek out the tiniest of improved fuel efficiency with little regard for the longer term health of the vavletrain.


I really don't know what to say. I can't prove that high-mileage oil is effecting mine, but it sure seems to have coincided with the start of my issues. Not sure about moving to 5W40. I'm certainly not the oil guru that a few on here have been over the years. I don't think it could hurt to try it I guess. I just go back to our VVT being so oil sensitive. At some point I'd think you can start having issues when it starts cooling off a bit outside.

IIQII

Yup that little change was quick.

Please don't take my responses as saying "you said...", they are more thinking things through and what may make sense. You have had some experiences I haven't and that I welcome.

I can say I know that it has had the recommended oil in it all its life. Almost every oil change was done at a dealership or by me.

The going to 5w-40 is just a thought. I have a few other things to check out. The wiring and the sensor are the first in my mind. I have ruled out the cam and the phaser as both are new. Couple that with the position(s) data and everything I have collected and that all seems to be what it needs to be. The weird part for me is that in researching this code it presents as a circuit issue. Some others have said it is a mechanical (I am referring to the motor city mechanic, I find his info useful). Even possible cause lists state possible mechanical reasons. Those listed seem to be ruled out by the new parts and data, but hey I could be wrong.

This has been an interesting exercise. Getting rid of each code as they appeared has worked without firing the parts cannon at it. Additionally, I got to know the Jeep much better. This code was out of the blue and caught me by surprise. It is not like the other codes that have a rather definitive list of possible root causes.

Ehhhh well, another road to venture down.