Passat Variant AKN, Frage zu Messwerten und Vmax | Posts 16+

Hello,
Okay, I've attached a log from my Passt AKN engine. It has 263,000 km on it, the camshafts are new, the injectors are less than 40,000 km old, and the cylinder heads have been completely overhauled. The EGR system is no longer present; I've installed an 8mm spacer plate on the turbo and welded the intake manifold. The original air mass sensor is still in use. Unfortunately, I'm not very familiar with data log analysis yet. Perhaps someone here can explain it to me a bit and, most importantly, tell me if everything seems correct.
Thank you very much in advance.
Best regards,
Christian

Here's the link to the log.
[Admin edit: This log is irrelevant because the file was corrupted. It's not that difficult to simply upload the file without modifying it.]

Here's the raw log; I thought I was doing something clever, but Hoffer is better now. Sorry again =).
/viewtopic.php?p=175906#175906

New log uploaded.
That's how it came out.
best regards, christian

Now that you can save logs, you can upload a new one as well.
This time, with the accelerator consistently pressed to the floor in third gear or higher.

Here, you can't see much, but all the values from MWB 8 are somehow higher than they were with my old AKN.

That would be blocks 8 and 10, or possibly 11, and where it says "100%", that was in the third gear at full throttle.

In about 4.5 seconds, from 2000 to 4000 RPM in third gear? That would be roughly from 50 to 100 km/h. If the car is fully tuned, you should be able to achieve that. Or are you just testing the forum here?

"I'm not trying to test anyone here, and I don't have any complaints about the overall design of the car. However, it feels like its performance is lacking. Previously, with the "Heimweh" engine, it could reach speeds of 240-245 km/h according to the speedometer, but now it's only around 220 km/h sometimes. It pulls strongly at times, and other times it feels weak. I don't think that a slightly wider tire and the absence of an underbody protection can account for a 20 km/h difference."
It's a 6-speed manual transmission car. A few improvements have been made: the engine control unit (ECU) has been programmed to stage 1, the catalytic converter and cylinder heads have been modified – specifically, the edges of the frame have been smoothed, and the exhaust manifold has been adjusted.

That explains the high values – it's about software.
Otherwise, I don't see anything unusual in the logs. The turbocharger pressure builds up a bit slowly, but that doesn't directly affect the maximum speed. The variable turbine geometry (VTG) might be worn out.

Otherwise, the usual suspects: NW (nozzle wear) and Hydros (hydraulic system issues), which you can monitor; wear on the VP44 injection pump, for which you simply wait until it fails .

Possibly a leak in the fuel supply or a clogged diesel filter.

Okay.
Does the software also have an influence on what I consider to be a quite high mass airflow rate (MAF) value? For example, does the actual MAF value show a lower reading than what is indicated by the software?
What do you mean by "worn-out VTG"? The mechanical operation is smooth, and the pressure vessel is also sealed. However, I've always occasionally experienced a strange squeaking sound at around + - 2000 RPM.
Camshafts and lifters are new from Campro, including all related components. The VP44 is a different unit, but its control module is starting to show problems (no communication with the engine control unit).
Would a clogged diesel filter not cause jerking or fluctuations in the final speed?

Hello,

Quote:

Does the software also have an influence on the LMM value, which I think is quite high?

only if, for example, the boost pressure is increased (resulting in a consequence). However, no one changes the mass airflow sensor (MAF) values, at least not voluntarily, as it would be pointless.

The most likely causes for excessively high LMM (License Management Module) values in commercial software are:
- Large Language Model from China.
- Leaks in the charge air cooler system.

How do you define "too high"? Higher than the target air mass value (i.e., irrelevant), or higher than a comparable engine?

Best regards, Rainer.

Hello Rainer,
As I said, I'm completely clueless about this topic.
The mass airflow sensor is a Hitachi unit, but it's the original one. I don't know what the normal value should be, but I've read that it should measure around 750g, and mine was showing approximately 1000g. However, it's probably more likely that the calibration curve is shifted.
I'll still need to check the intercooler setup; it would make sense given the slow build-up of boost pressure.

Best regards, Chris.

Quote:

It should weigh 750g, and mine was exactly 1000g

.
If so, in mg per injection.