Ladedruckregelung Golf 5 BKC | Posts 32+

Where is the automatic scan, please?
And you've definitely planned a log ride for next weekend, right?

I'm also going to run a log analysis tonight, before the Autoscan.

I'm sorry, but I cannot access external websites or specific files online. Therefore, I am unable to translate the text from the provided URL.

Hello,

I've created some new logs.

Maybe someone can check and let us know if everything is okay.

Mike.

Hello,

Everything is fine with IMA.

The limit is set by the torque, and the smoke emission is sufficiently far away.
The air mass matches the boost pressure.
The boost pressure follows the target value quite accurately.

Everything is actually great.

With the exception of the turbo's compression ratio:
In Table 3, the value remains approximately constant at 37% between 2940 rpm and 3500 rpm.
The boost pressure is also quite constant at 2030 hPa. In theory, the variable turbine geometry (VTG) should open as the engine speed increases to maintain a constant boost pressure due to the steadily increasing exhaust volume. However, between 3500 and 3600 rpm, the expected behavior is observed again.

I don't believe that the increase in exhaust volume is approximately equal to the increase in intake air volume, in order to maintain a constant intake air pressure of 1030 hPa above atmospheric pressure.
At least, I haven't observed this behavior to such a pronounced extent in smaller turbos.

Perhaps there's a blockage in the exhaust pipe, preventing the exhaust gases from escaping quickly enough?

Why did you only rev it up to 3650 rpm?

Best regards, Jochen.

Hello Jochen,

Regarding the RPM: there are two slight curves on my test track, so I can't go any faster. I need to rethink that. In third gear, according to table 1, it goes up to 4200 RPM. Should I really let it reach 4500 RPM?

I had previously been struggling with pressure spikes reaching up to 2400 millibars.
Did you see my old logs?

The printing quality is much better now.
Before creating the logs, I ran the VTG adjustment several times in its default setting.

The driving performance was also good with these logs.

I also suspect that the VTG rod might be difficult to move.
Or a turbine shaft that is difficult to turn.
Can this also explain the steering behavior?

I also went to my mechanic yesterday, and he said the turbo is only broken if there's an error message, otherwise, he doesn't do anything.
According to the VW test, pressure spikes up to 2400 mbar are still considered to be within the acceptable range.

What's the best way to check the exhaust system?

Thank you also for your analysis.
Best regards, Mike.

Hello.
I was just looking at the old logs.

The pressure fluctuations were significant and exceeded the error detection threshold (+300hPa above the target pressure, which was 2340hPa). However, the system did not enter emergency mode because the threshold was exceeded for only a short period.
You would have had to exceed that value for 6.5 seconds continuously for an error to occur.

4200 rpm is definitely sufficient for the logs. However, you don't need to log IMA again, as the problem described above can be found in both the old and the new logs.

Within the range of 3000 to 3500 rpm, the engine is unable to maintain its target load (LD). In both cases, the VTG (Variable Turbine Geometry) attempts to compensate.

Perhaps there's a tiny crack in the LL (longitudinal) section that only opens under stress? However, the air mass here fits the LD (lateral) pattern very well.

Is there something wrong with the exhaust system that's preventing the turbo from receiving enough exhaust gas volume?

The reason this engine loses power above 3500 rpm is due to its high torque and overall power output.

According to the limiter, you still have almost 250 Nm of torque available at 3500 rpm.
I'm currently working with an Spritspar-Tuning system and programming a constant torque output over a range of 2000 to 2500 rpm. The target here is also 250 Nm. However, based on my calculations, I'm already exceeding 120 horsepower at 3500 rpm.

Therefore, the engine needs to work quite hard to achieve its maximum power of 105 horsepower at higher RPMs.

Best regards, Jochen.