Problem Solved: Simple Solutions & Tips | Posts 16+

Happy New Year to all you diesel mechanics!

I bought and installed a brand new VAG turbocharger (038 145 702 J) over Christmas because I didn't want to subject the engine to any longer distances with the defective turbocharger!

The LD regulation is now working properly again (with minor limitations).
The excessive smoking that was very noticeable at full load is now completely gone! .

The LD (Low Drag) setup is already very impressive: with the slightest movements of the accelerator pedal, you can make the LD quickly increase or decrease its speed.

Now, let's talk about the 'minor limitations':
Under full throttle, the boost pressure exceeds the limit of 1.25 bar at approximately 4000 RPM in 5th gear. Instead, it stabilizes at around 1.4 bar (as long as the accelerator pedal is fully depressed).
I assume that the TV (torque value) of the LD (load detection) control loop is at approximately 95%, meaning that the LD is completely reduced (unfortunately, I don't have any logs for this speed range, but the LD control worked perfectly during the logged trips).

Is the loader being overwhelmed/saturated by the large exhaust flow, to the point where the completely open VTG 'vanes' can no longer effectively limit the load?

Should the fuel injection amount be reduced (adjustment of level 1)?

Should the other loader be taken into account in the pre-tax vehicle calculation (or in any other vehicle calculation)? Stage 1 was adjusted with the original loader.

I would like to express my sincere gratitude to everyone involved for their help with my problem!!!!!!!!!!

Best regards, Kassen.

oldewurtel wrote:

The boost pressure, when using full throttle above approximately 4000 RPM in 5th gear, is no longer limited to 1.25 bar. It settles (as long as you are using full throttle) to approximately 1.4 bar. I assume that the TV of the LD control loop is at approximately 95%, which means the LD is completely reduced. Is the loader

overfilled/saturated by the large exhaust flow, to the extent that the completely open VTG "wings" can no longer effectively limit the LD?

Quote:

If your assumption is correct: yes.

Should the injection amount be reduced here (adjustment of stage 1)?

Quote:

In principle, yes, but perhaps there is still some room in the software to further increase the VTG-open limit of the throttle position sensor (!).

Level 1 was adjusted using the original charger. }And the one that was purchased later is a different type?

ulf wrote:

Quote: Level 1 was adjusted to fit the original charger. And the one that was purchased later is a different type?

Given that the AFN is 96 and the Turbo has a 038 number, I'm quite certain.

m;

Hi Kassen,

Sorry for not getting back to you sooner regarding the charger offer. No one was available at the supplier's office around the turn of the year. :-/
If the boost pressure remains at 1.4 bar even after a few seconds of full throttle, then either the turbocharger is unable to handle the exhaust flow, or, if it was a variable geometry turbocharger, the guide vanes are either incorrectly adjusted or not opening sufficiently.

Best regards, Rainer.

Hello Rainer,

Unfortunately, I had to purchase a brand new (meaning not refurbished!!) VAG turbocharger, part number 038 145 702 J (standard equipment on the 130 HP AWX/AVF engines), because, as described, I didn't want to continue to stress the engine with a faulty turbocharger.
So, it definitely isn't the original loader that was installed (as dieselmartin correctly suspected, the original model is VNT15).

I would have really liked to buy the new ATL from you . Unfortunately, the timing was unfavorable for everyone involved.

Regarding the topic of 1.4 bar of boost at full throttle:
Should we adjust the characteristic maps on-site again, or can you modify the engine control unit (ECU) parameters using the loader data (see above) and your extensive experience, and then send me the updated file via email?
The further 'processing' of the data would not be a problem . Should I send you the data that I currently have??

If needed, I can also arrange for specialized log transportation.

Best regards, Kassen.

Hi Kassen,

Quote:

Should we adjust the characteristic curves on-site again, or can you modify the KF (calibration data) using the loader data (see above) and your extensive experience, and then send it to me via email?

theoretically yes, but practically, the fact that the boost pressure doesn't regulate itself even after a few seconds is concerning... by the way, the now-installed turbocharger provides a few more horsepower .

Best regards, Rainer.

Hello Rainer,

How can I eliminate your 'thoughtfulness' ? Perhaps through a logic trip?

I am very confident that, regarding boost pressure, everything is now essentially in a new state (hoses are new or have been checked for vacuum, the vacuum pump is working properly, the N75 valve is brand new, and the wastegate actuator (ATL) is brand new) .

I 'felt' that the pressure was around 1.4 bar for about 5-10 seconds (at 180 km/h, that feels like a very long time).

Thanks to the temporarily installed LDA (Linear Density Analyzer) with a painted 'red' area starting at 1.25 bar, I can very well observe the normal operating processes (full throttle at approximately 1500 RPM -> the LDA quickly rises and then seems to be held at approximately 0.7 bar, meaning it is being regulated).
Even at full throttle, approximately 3000 RPM (in 5th gear), the turbocharger will be 'held' at 1.25 bar, meaning it will be regulated.
Around 4000 RPM, at full throttle, the pressure reading is approximately 1.4 bar. The LD (likely referring to a pressure indicator) only decreases when the throttle is slightly reduced.

Or are these extra 'horsepower' already 'over'-mobilized by mistake, because the vehicle didn't quite 'work' properly when it was being tuned on site back then?
Back then, you were trying to connect to a local device (LD) that wasn't establishing a connection quickly enough.
(Looking back, I can definitely say that the old, original ATL was at its end!)

Can this be easily determined using a diagnostic tool or VAGCOM to get some certainty?

Should I send you the Flash content via part number so you can take a look?

Best regards,
Cash registers.

Hi Kassen,

Please send me the memory dump data from the memory modules. The LD regulation definitely needs to be engaged, and I suspect there's something else wrong.

Best regards, Rainer.

Hello Rainer,

I just sent you an email with all the necessary information ([email protected]).

Best regards, Kassen.

Hi Kassen,

The files you emailed me are unfortunately corrupted. It's possible that one or more data or address lines didn't make proper contact during the reading process.

Just provide your VAG part number and the software version, as I can't find any information about your software.

IMHO, the problem lies with the charger itself, because if the TV (tank vehicle) is stuck at the "top" (>85%) of the VTG (vehicle tracking and guidance) control range, it means the MSTG (main system) is trying to lower the charging level, but it's not working.

Best regards, Rainer.

Hello Rainer,

I sent them an email.

Best regards, Kassen.