AFN Turbocharger Control: Troubleshooting Guide

Hello everyone,

After a long time of not being active on this forum, and unfortunately having less time for it lately, I have a rather unusual question.

My Ibiza 6K1 with the AFN engine, which now has 225,000 km on the clock, is experiencing a very strange loss of power, especially in the first two gears.
According to the LDA (likely referring to a dynamometer reading), I'm barely reaching 4,000 RPM when accelerating from a standstill, and my actual boost pressure is only what I normally have at just under 2 bar. Top speed isn't a problem, except for the crazy overboosts I experience if I momentarily lift off the throttle.

VTG is doing great, and I also tried an LMM; I happened to have one lying around. I also had an EPW, but that's not it either.

Could it be that the problem is fundamentally related to the set screw of the charger?

Vacuum pressure, N75 valve, and exhaust system: are they all okay? Does the variable turbine geometry (VTG) always reach its full travel? It's possible that there's a vacuum leak, and the pre-injection map is negatively affecting boost pressure at low RPMs. Try tightening the VTG actuator and see if it builds more pressure. However, it will likely go into limp mode then.

In my opinion (!), if the problem were related to the screw, there shouldn't be a significant overshoot, but rather just a delayed or sluggish pressure buildup. The regulation should be normal from the point where the pressure is applied...

Connect to control module 011 using VAGCOM and check the vacuum pressure, as well as visually inspect the VTG rod.

Otherwise, create a 003-008-011-3.Gang-1500..4000 log, process it, and upload it here.

Without these details, I would say that something is broken .

m;

Sure, I understand. Please provide the text you would like me to translate from German to English.
here: https://community.dieselschrauber.org/en/viewtopic.php?t=12864&highlight=asv+ladedruck+begutachten

Since it's related to the topic – what do you think about a vacuum pressure (before regulation) of 760 mbar?

How do you remove the plastic connector from the vacuum hose at the power brake booster in order to disconnect it?

What do you mean by "what do we think about..."?

I think that's good, let's auction it off immediately .

Okay, seriously now:
I think that's good. The ASV (absolute static vacuum) value I once measured was -0.8 bar, as you can see in this ZIP file.
Okay, I'm ready. Please provide the German text you want me to translate into English.
However, the "-0.8" setting was located directly behind the control, which was initially set to "full material" in module MWB 011.

Okay, please provide the German text you would like me to translate into English. I will only provide the translation.

However, the '-0.8' setting was located directly behind the control, which was set to 'full material' by default in module MWB 011.

m;
Exactly because of your article, I asked .

If the Vtg is set to fully open, I only have -0.6 bar (after the regulator). You wrote that it should reach at least -0.8 bar before the regulator. With -0.76, I don't even reach your specified value.


...how can I remove this plastic corner piece now? Just pull it off?