We finally have a resolution after more than a year of nightmares in trying to diagnose our 2017 Jeep Wrangler Unlimited Rubicon issues with engine codes and performance problems. There are very few answers to these codes on the internet, we think this is truly the first honest diagnostic answer to this problem! (After 3 months now, we believe we can confidently say this was indeed the resolution.)
There are very few real answers to these codes on the internet! We think this is truly the first honest diagnostic answer to this problem! We learned about Pine Hollow Automotive Diagnostics through YouTube suggesting his channel in the recommended feeds feed. We were impressed with the scientific approach Ivan Temnykh, owner and automotive diagnostician, took with his various “case studies” that he published on YouTube. We reached out to him and set up an appointment to look at Rubi our Jeep when we headed east in the fall of 2023. Rubi’s problems have now haunted us for a year since the first codes were thrown in September 2022. Ivan not only has the same tools many mechanics have at their disposal, but he actually understands the data those tools stream out. He worked through the systems and looked at the problem from a scientific approach instead of the “gut reactions” we were getting from other shops.
This problem cost us around $3,000 total in repair bills from the beginning to the end. This includes renting cars, a ludicrous windshield replacement on a rental car, several “parts cannon” approaches to the problem, and finally the out-of-the-way miles to get to Pine Hollow Automotive Diagnostics. We are very pleased with this outcome, thank you, Ivan!
The Fix, Final Conclusion
Spoiler Alert!
Since you probably won’t read or watch to the end, what was the source of the problem? The final resolution turned out to be a missing oil gallery plug, under the valve cover, on the oil gallery.
Was the plug ever there in the first place? Did it have “lock tight” on it from the factory? Or did the bolt turn out and disappear into the oil pan? We have not done more research into this, but we do plan to have a trusted shop check it out when we get back to Wisconsin in the spring.
Definition from Auto Zone: “OIL GALLERY” – Passages drilled or cast into the cylinder heads, engine block, and crankshaft to receive pressurized oil from the oil pump for distribution throughout the engine.
The Video Series
You can enjoy the entire YouTube video series or skip directly to the answer here. There are three videos you need to check out! We are very fortunate that Ivan warrants his work and he was awesome to work with on this find!
Some of the comments to the videos were constructive and supportive, others were just fearful of the ducks!
| @davidshettlesworth1442. 3w ago – Thank you for this excellent video. Please let the Jeep dealer mechanics and all Jeep DIYers out there hear what you have gone through (a living Bad Place) with the missing bolts causing the throwing of the codes. This is big news and it seems a common problem for this engine! Happy that you were victorious! “Shout the news from the mountain tops! Job Well Done Sir! Carry On! |
| @throttlewatch4614 4w ago – I wouldn’t work on it just based on the ducks ^ @jilbertb 4w ago – Those represent a “kudos” for such a sweet ride… |
| @advanced leveldiagnostics 1 mo ago – Wow Crazy find! Do you think it’s possible to check these with a camera or the valve cover must come off? ^ @PineHollowAutoDiagnos… 1 mo ago – Valve cover must come off. |
| @paulpaquette1961 · 1mo ago – Well Ivan it certainly looks like you had ALL the ducks in order! |
Time Line of the Saga
Sep’22: Engine Codes Begin
P0345 Camshaft position sensor circuit - bank 2, sensor 1 P0349 Camshaft position sensor circuit intermittent - bank 2, sensor 1 P0390 Camshaft position sensor circuit - bank 2, sensor 2 P0394 Bank 2 camshaft position sensor 2/2 circuit intermittent P06DE Engine oil pressure control circuit stuck on
In September 2022, we had our first P05DE oil pressure switch code. We dismissed this as related to the Wisconsin weather turning code. However, a few days later that reset, and then our first P0394 appeared and the the saga began with the camshaft sensors. Our mileage at this time was around 75K.
Oct’22: Replace Sensors, Wiring, Computer?
We were traveling to Virginia that week and were able to find an offroad shop in the DC area that could get us in to see it. The P0390 was now also appearing by this time. They replaced both of the camshaft sensors and we were good for a few days. Then bam, P0390, P2538, and C121C fired off together.
P0390 Camshaft position sensor circuit - bank 2 sensor 2 P2638 Torque management feedback signal performance C121C Torque requested not possible
We get the Jeep back into the same shop and they swap the sensors from one bank to the other. The problem stays with the same bank, the assumption is that the wiring is at fault.
A local Jeep dealer is recommended by this shop and they can get us in the same day. They also conclude the wiring is bad and recommend replacing the wiring harness. However, “due to COVID supply chain issues,” the parts may take 18 months to acquire and it will be over $2K! (Prepaid of course!) Instead, they recommend replacing the computer to eliminate any issues with that first.
Nov’22: Cylinder Misfires, New PCM
Driving down through Knoxville to the Smokey Mountain National Park a whole new set of codes and problems suddenly appear. We pull off the highway and sit in a gas station parking lot trying to figure out if we need to have the Jeep towed back to our RV park or if we could even drive home safely. So we decided to limp home and the remainder of November is with the Jeep parked while we deal with finding a new computer.
We finally made it to Florida later in the month by our normal towing of the Jeep behind the motorhome. Plus, we finally got the rebuilt PCM (after three tries) to experiment with in the Jeep. This was a complete disaster. This caused a completely new set of codes and mess to the situation. We ended up replacing the throttle body and the accelerator pedal sensor switch based on this fork in the road. It was a great thing there were two parts stores within biking distance of our RV Park!
We then towed the Jeep to a shop in Winter Garden, Florida, with our rental vehicle! They put the old computer back in and got it running again. Plus this shop found several other issues with the wiring harness and some cylinder compression issues. The issues with the wiring harness were probably related to the dealer that replaced the alternator and wiring harness on warranty as we became the proud new owners of this Jeep three years prior. The shop believes all of this is from shotty work by that warranty mechanic that led to the chaffing issues, etc. These issues were addressed and we drove the Jeep for about a week before the same P0390 and P0394 combination re-appears. All of that work as we later learn had nothing to do with the real problem, but this was completely ancillary. It might have been some chicken or egg-related issues to the actual problem.
Dec’22: Replace the Engine?!
So back to the same shop in Florida, where they ultimately decide the entire engine needs to be replaced. Oh, that will be $10K, and getting an engine will be about a year’s wait due to “COVID supply issues!” We opt to not do anything at this time.
Jun’23: YouTube Repairs
A co-worker suggested a shop in New York that he was watching on YouTube, from there YouTube suggests the Pine Hollow Automotive Diagnostics channel. We watch dozens of hours worth of videos. We become more and more impressed with Ivan and we reach out to him through his website. We contemplate hauling the Jeep out to him right away, but we cannot get away over the summer due to work-related commitments. We continue to watch and wait, and hope, that the fall will be the final answer.
Jul’23: OEM Parts
The codes will usually fire at the start of the engine, but at this point, we have non-OEM camshaft sensors. Ivan finds in many of his cases that cheap non-OEM equipment will cause problems. Early in our saga, the first shop mentioned that these sensors were about 50/50 hit on whether they would work.
We had already made our appointment with Ivan to see him in the fall, we were not going to show up there with non-OEM parts in the Jeep! We replaced them on 4th of July and the problem changed. Now the Jeep will start without the code firing but it will then fire about 9 minutes later. This would happen regardless of weather, starting from cold or other conditions.
We believe later, that this was likely related to software giving the problem some time before the computer would consider the problem worthy of a code under these conditions. With the non-OEM sensors, the problem was probably more pronounced and out of tolerance faster causing the code to appear at start up.
Sep’23: Ivan Fixes It!!!
If you watch the three videos above, this was over about three weeks. First Ivan diagnosed the problem as the camshaft itself. We authorized him to purchase the camshaft and we would come back in two weeks when the part was in stock and he had time to get it opened up.
The second and third videos were over four days. He first replaces the camshaft, but the problem appears again. Like before, at about 10 minutes into the test drive the code reappears. He then keeps the Jeep at his garage where he pours over oscilloscope readings and CAN bus values.
Ivan stood behind his warranty and did not charge us for the camshaft or the installation of it. We did pay for the final “custom plug” (bolt) and lots of hours of diagnostic time.
