VGT Actuator Test - AlphaOBD

[TelosAlpha]

Hi everyone!

I detled my 2016 1500. Everything is fine until I started chasing an underboost issue (P0299). Using TopDon scanner tools I noticed that the VGT position called for and actual were very different and the airflow the engine should be getting is about 1/3 of whats called for.

I have managed to troubleshoot this down to needing a bi-directional rig to test. I have the paid version of Alpha and the MX+ is in the mail.

I have never done directional anything via OBD.

I want to tell the engine to try and move the VGT actuator on the top of the turbo so I can see if the thing even moves or trys to move. Hoping its:

1 - loose connector
2 - stuck actuator arm due to buildup
3 - bad actuator

Any help or guidance greatly appreciated. I have searched around for some tutorials on YT but EVERYTHING is for changing and calibrating the actuator on Cummins.

T

 

[BillySoot]

I just went thru all this. My alphOBD is how I diagnosed that it flat lined as I had no codes just the lightening bolt. Seems all the "P" codes were turned off in my STG2 tune Guess what Ram won't do? Sell just the actuator. So a complete assembly it is.
My Grand Cherokee was a bear of a job, pick ups are worse.

 

[TelosAlpha]

I still have the P0299 - so my tune isn't blocking anything.

I am pressure/smoke testing the exhaust today to see if there is a boost leak or any leaks in the downstream components.

I ran the actuator yesterday from AlphaOBD and it moved perfectly, so either the turbo is plugged up or on the way out if there are no leaks.

Either way its a turbo job, and I aint doin that!

On to the local guy who works on delted diesels LOL..

 

[BillySoot]

Good you got it to move. Test the intake flaps for movement?
Smoke testing will expose any leaks, good next step.

 

[TelosAlpha]

OK - smoke tested the exhaust (has stock muffler and delete kit straight pipe tot he turbo) and saw a small exhaust leak through a pin hole in the muffler, and a bigger leak in one of the joints.

Going to weld, tighten and do a boost leak test next.

 

[TelosAlpha]

OK.

/TLDR - Does anyone think a VGT actuator change is the solution here or is this a blown turbo?

Turbo SOUDNS good, fantastic even. Same as it did pre-delete.

Pressure test - solid. Not a peep from anything. Nothing loose. Nothing leaking.

Welded up muffler and tightened the joint where it was leaking and smoke tested - no leaks anymore.

Ran the truck and got the P0299 code again.

Hooked up TopScan (Alpha wont run this test for some reason) - ran the boost actuator test. Verified visually that the actuator is moving. It rotates farther if the percentage in increased so as best I can tell it working, perhaps not calibrated but working.

As you can see below, the requested percentage, what the actuator is called to do, what its actually doing, and the measured postion are all different with measure always being zero.

Of note, after the P0299 is thrown, the VGT Required goes to 10%, but the measure stays at 0.

As I say in the video, I think the position sensor inside the VGT actuator is gone, thus needing a new module (which I can pull off, if I can find one used, I have a line on a few) or the turbo is failing and its a turbo job.

Anyone with experience here or any of the diesel mechanics opinion would be super valuable here!

Video of the test.

- YouTube

Enjoy the videos and music you love, upload original content, and share it all with friends, family, and the world on YouTube.

youtube.com

 

[BillySoot]

Data logging actual and target settings while running up the gears will show a torque limit until like 3rd gear as it starts to pull harder and they should match better. It's like tab 6 or 7 in alpha OBD.
If you have a handheld tuner- upload the stock tune and then reload the STG you are running.
That's what I did and it worked until it faulted due to the Banks intake and spacer, no electrical connections. I don't get a code just lightening bolt ....
A few times actually and the last time the actuator said 46% on Alfa OBD
I'm scouting around for an actual tuner (SFT tucked his tail and ran, the slow kids that are chasing SFT crumbs, Optimus, just ghosted me after I sent them my tune) that can actually custom tune and not just a resell canned tunes....

 

[TelosAlpha]

Thanks for that! Appreciate the dialog here.

I am using a Powergate 3 to push the tune. I'll go back to stock and returned and see what happens.

FYI I get the P0299 and the Thottle Service error on the dash.

I have sent out the stuff I posted here along with some CSV dumps from Alpha to the shop I got the tune from.

Hopefully they have some ideas or angles to chase down.

 

[BillySoot]

Let us know how this moves forward

 

[TelosAlpha]

OK, found a whole turbo with 150k on it for $400 CAD. ITs on the way. Ill grab the actuator from that and swap them and start on the rebuild of the rest of the turbo.

Yesterday I also removed the up pipe that fed the EGR. I had it capped on the top but through research discovered that it sometimes rots out. Mine was fine but now I have much clearer access to the top of the turbo and its removal will make life easier for the actuator swap.

I wish I could trust ramps. I do all this with the truck in OFF ROAD 2 LOL and a crawler.

I found a guy in Ottawa that is helping me over the phone. I will likely take the truck there if I need the cab taken off for the turbo replacement. Ill update here with results as thing progress.

 

[BillySoot]

Dig in and keep wrenchin'
The high up you get the vehicle, the easier it is.
Like taking the exhaust pipe off the turbo.
There's loads of info on "cribbing" on the etherwebs, some as high as 2 feet...

 

[TelosAlpha]

UPDATE -

Just got the word back from the tuner that a weak fuel pump can sometimes cause this issue with a 20+ horsepower tune.

They are going to send me back a stock 0 horsepower upgrade stage 2 delete tune and if the resolves the issue, I can use that tune until I swap out my fuel pump.

No idea how the data I got from the actuator comes down to a fuel pump, but a pump is something I can tackle no issues, and WAY easier than a fricken turbo.

Updates to follow.

 

[BillySoot]

Have you had the High pressure fuel Pump recall done?

 

[TelosAlpha]

Whats that recall number?

Just out roadtesting the new tune

 

[BillySoot]

Z46

 

[TelosAlpha]

Gotcha - yes that has been done.

I added the new tune, got slightly farther than the +20HP tune and it threw the code again. Just to be safe I monitored the fuel stats on Alpha and they are very tight. Its not the fuel pump, or supply being weak.

I think I am on the hook for an actuator swap.