WK Grand Cherokee Diesel

[ericjon262]

I wonder how much EGR flow is excessive, and if it could have an effect on turbocharger performance. is the EGR downstream of the turbo? a clogged DPF would cause reduced turbo performance, and potentially a higher flow through the EGR, or at least in my head that could happen.

[pmbrunelle]

Looks like a MAP sensor may be the next step on the WKGC. RockAuto lists an "Intake Manifold Differential Sensor" which looks like a MAP referenced to something other than ambient. Hmmm...

https://www.rockauto.com/en/moreinfo.ph ... 43&jsn=965

Can't you just follow the vacuum lines and see where they go?

[The Dark Side of Will]

I wonder how much EGR flow is excessive, and if it could have an effect on turbocharger performance. is the EGR downstream of the turbo? a clogged DPF would cause reduced turbo performance, and potentially a higher flow through the EGR, or at least in my head that could happen.

Haven't gotten that far yet, but that's a possibility. However, I would sort of expect it to act like a gasoline engine with a clogged cat, which is to have no power under any circumstances. Engine power when it's not on reduced power mode seems fine. I did a power braked launch and it scratched all four. It's flowing air and making boost, it's just not matching the curve that it's supposed to have. That's why the VNT actuator can cause the problem. If the VNT actuator is stuck all the way open, then the turbo acts like a big turbo and the boost curve changes, which causes it to set the code. Peak boost can be just as much as it would be with the actuator functioning, an the car could drive ok, while only missing a bit of low end torque, but it still sets the code.

Can't you just follow the vacuum lines and see where they go?

Implicitly, that's part of the steps to troubleshooting the MAP sensor.

[The Dark Side of Will]

Sooo... Umm... Duh.
I was looking under "Exhaust and emission" in RockAuto and saw the differential pressure sensor. After some extra googling of the MB PN printed beside the Mopar PN on the photograph on RockAuto, I determined that is the DPF differential pressure sensor.

Looking under "Fuel & Air" showed me the actual MAP sensor, which is only $26 for an actual Bosch unit... I'll order one so I have it this weekend. It looks like it bolts to the manifold and has an o-ring, so there shouldn't be any plumbing to screw it up.

[The Dark Side of Will]

The MAP sensor did not fix the problem. Next up is boost leak.
It occurred to me that I may have reassembled the turbo piping incorrectly, particularly at the joint to the "kidney" intake resonator bolted to the front of the engine. The o-rings in the joints probably also need to be replaced after 211,000 miles. The kidney seems the most common source of boost leaks, due to it cracking over time.

This is the kidney:
https://www.idparts.com/turbocharger-re ... 12312.html


Along with an aftermarket replacement:
https://cb-engineer.com/products/turbo- ... elete-pipe


And a page on DIY fabbing a replacement:
http://www.engineeredobsolescence.com/2 ... ification/

There is also a CAT hose that can be cut down to work.

The shape of the unit and the relationship of the connections is not hard to duplicate... it's basically a 30 degree bend with a leg on one end. However, the joints are not hose barbs, as can be seen in the photo from CB Engineering above. This makes adapting a replacement somewhat gimmicky.

[ericjon262]

I looked at the pics of your engine, where exactly is that part on there?

[The Dark Side of Will]

It's off the bottom edge of the one engine bay pic I posted... Where the turbo outlet pipe goes down over the front of the engine between the engine and radiator on is way to the intercooler

[The Dark Side of Will]

Going to the Jeep forum to look for the proper assembly order for these parts:



The 2 3/8 x 1.5" reducer coupling arrived and we set it up at the turbo inlet and pumped a regulated 20 psi into it. It's hard to tell, but we can hear some hissing that I think was coming from the upper joint at the kidney, where the hard pipe from the turbo outlet hooks up. When I took that pipe out as I was replacing the fuel filter, that joint popped apart when I tugged on it, so I never saw the correct assembly order.

[The Dark Side of Will]

*THIS* is the correct assembly order



The turbo side of the kidney should look like this prior to installing the tube



I reseated the turbo end o-ring on the turbo outlet. I tried re-installing the tube, checked for leaks again and found that the turbo to tube connection was STILL leaking. I took it apart and found that the tube had CUT the o-ring as I was installing it. WTF? How bad is this joint design that that can accidentally happen when someone is very carefully assembling it? The plant from which my dad is semi-retired, by the grace of God, had a -225 o-ring, which worked. I oiled the entire o-ring AND both the turbo barb AND inside of the tube before trying to assemble it again. That finally worked without damaging or pinching the o-ring.



Once I fixed the boost leaks *I* made, I found this.



This is the intercooler to engine hose. Also, everything around it had been sprayed down with oil.
I've done some googling and have 7 or 8 part numbers between this hose and the Kidney-to-intercooler hose. What are the most current two part numbers? Is there a brand other than Mopar that is worth trying? I'm thinking I'll get both hoses and put the other one on the shelf until it splits as well.

[The Dark Side of Will]

Wheeler finally said they were expecting the first hose today and the second tomorrow, then would get both on their way to me.

[The Dark Side of Will]

Wheeler finally said they were expecting the first hose today and the second tomorrow, then would get both on their way to me.

They finally arrive yesterday, but since this is a drill weekend (maybe my last?) I won't get to play with them until next weekend.

[The Dark Side of Will]

I placed the order on 4/19, the hsoes were finally delivered on 5/14. Of course that was my drill weekend, so I wasn't able to do anything with them. So I wasn't able to install them until last weekend, >1 month after placing the order. I should have ordered the silicone versions from JeepChryslerParts on eBay.
However, after more than a month, I can now authoritatively and with confidence answer the question "Where my hose at?"



That's the left (Turbo to intercooler) hose.
Here's the right (Intercooler to engine) hose:



Here's 2/3 of my diesel fleet:



I put ~100 miles on the WK that day going to a longtime friend's kid's birthday party, grocery store, hardware store, etc and generally tooling around. That evening it suddenly starting giving problems. The transfer case dropped out of gear, then tried to get back into either high or low range, repeatedly, randomly. I thought the "implausible input from ESM" code would cause the system to ignore spurious inputs from the T-Case actuator encoder, but apparently, as soon as it gets a plausible input, it acts on said plausible input, which means that the flakey encoder can cause it to spontaneously shift out of gear while driving through town.

I knew I needed to replace the actuator because of the code, but didn't know it could spontaneously cause problems like that.

Are remanufactured actuators any good or do I need to go straight to new actuators? Are there any brands to avoid? RockAuto lists Ultra-Power for $165 and Dorman for $230. I tried a Dorman replacement glow plug controller on my Benz (same unit as the WK) and the lid popped off when I took it out of the box, so I'm not sure Dorman has these more complex assemblies figured out yet, although they do a good job with piece parts. Given that, I'm super sketchy about Ultra-Power at 30% cheaper...

EDIT: Oh yeah... Is Mopar or a junk yard the only source for hood insulation? Mine's fallen down and the retainers pulled through the mat.

[The Dark Side of Will]

Ordered a new Dorman T-Case motor from Rock. Rock doesn't carry the Cardone rebuild and PartsGeek couldn't tell me anything better than 3-7 business days for shipping. I'll be able to install this weekend and that should give me back low range and full 4wd capability.

[The Dark Side of Will]

New T-case motor works great and fixed the 4WD system problems. That created a new problem in that I damaged my rear fascia seeing what the Jeep would do driving through drainage ditches and such.

One thing I hadn't heard before is that low range locks the T-case. I had not read anything definitive about that. I was wondering how one motor handled both the T-case clutch application AND shifting duties while still being able to apply the T-case clutch in 4Lo. The answer is that it does not. I @$$ume that when the motor turns one direction, it applies the T-case clutch, then as it turns back through the neutral center position it releases the T-case clutch; then as it turns the other direction it moves the shift collar into low range AND locks the T-case with one operation.

Some busy-body VA state pooper gave me a ticket for expired inspection. I was going to get it inspected anyway once I was satisfied that it's reliable enough, but now I have to move that timetable up. Thanks @$$hole.

[The Dark Side of Will]

Some busy-body VA state pooper gave me a ticket for expired inspection. I was going to get it inspected anyway once I was satisfied that it's reliable enough, but now I have to move that timetable up. Thanks @$$hole.

Got a Mopar front plate bracket on order because the VA General Assembly is full of overbearing authoritarian busybodies too ignorant to get that the rest of the country dropped front plate requirements years ago, AND because VA State poopers are apparently incentivized to be dicks to people they don't know about things that don't matter.

[ericjon262]

Some busy-body VA state pooper gave me a ticket for expired inspection. I was going to get it inspected anyway once I was satisfied that it's reliable enough, but now I have to move that timetable up. Thanks @$$hole.

Got a Mopar front plate bracket on order because the VA General Assembly is full of overbearing authoritarian busybodies too ignorant to get that the rest of the country dropped front plate requirements years ago, AND because VA State poopers are apparently incentivized to be dicks to people they don't know about things that don't matter.

must be a thing with states that initials end in "A" WA also has front plates, I never got asked about them though, as I maintained FL registration. being active duty did occasionally have perks.

[The Dark Side of Will]

must be a thing with states that initials end in "A" WA also has front plates, I never got asked about them though, as I maintained FL registration. being active duty did occasionally have perks.

I'm leaning toward "It's just totalitarian jerks" myself.

[ericjon262]

must be a thing with states that initials end in "A" WA also has front plates, I never got asked about them though, as I maintained FL registration. being active duty did occasionally have perks.

I'm leaning toward "It's just totalitarian jerks" myself.

lol, fair.

you see this? I'm so torn, I hate the fad, but I also hate laws restricting my freedom to be a moron....

https://www.thedrive.com/news/40913/nor ... 5Rx2akUyjE

[The Dark Side of Will]

lol, fair.

you see this? I'm so torn, I hate the fad, but I also hate laws restricting my freedom to be a moron....

https://www.thedrive.com/news/40913/nor ... 5Rx2akUyjE

Bleh. Ok, Boomers.

[The Dark Side of Will]

lol, fair.

you see this? I'm so torn, I hate the fad, but I also hate laws restricting my freedom to be a moron....

https://www.thedrive.com/news/40913/nor ... 5Rx2akUyjE

If they'd just aim their headlights, most of the annoying aspect of this would go away.
Obviously, the guys who spend $$$$ like in the headline photo are pretty rare... but they're the ones who get shown in the headline photo and get "people" to think that's what everyone who does this does. People are stupid.