Intermittent T4 Performance Issues / Troubleshooting

First of all, hello.
And a big compliment from me!
Great forum, it's definitely been helpful to me on more than one occasion.
Now, let's get to the point of my inquiry.

The problem concerns a T4 Automatic transmission with engine code AU, manufactured in 2001. It occasionally exhibits a lack of power. This manifests as the engine only reaching 3000 RPM, and the maximum speed being limited to 100 km/h.
Als Eintrag im Fehlerspeicher natürlich "ladedruckregelung regelgrenze unterschritten" als sporadicher fehler.und seit neustem der "g62 mit kurzschluss nach plus".Das erste mal trat die Story im märz dieses Jahres auf worauf ich dann die unterdruckverschlauchung erneuert und das magnetventil ebenso habe(hatte schon öfter mit defekten magnetventilen und deswegen getauchten ladern zu tun). Darauf Liefer er dann auch wieder 500 km normal. Beim erneutem auftreten Erneuerte ich dann den LLm da die angesaugte lm nicht stimmte und den Luftfilter.Auch das AGR Ventil reinigte ich. also dann der fehler zum wiederholten mal Auftrat erneuerte ich den turbolader da es das letzte seien konnte was ich mkir vorsellen konnte. Aufgrund versteckter Unterdruckleitung erlebte ich auf der Probefahrt ein fiasko was sich aber zum Glück zeigte. ok das fahrzeug lief wieder.doch nach ca 1000 km wieder das selbe keine Leistung! nach einiger suche habe ich dann festgestellt das der Saugschlauch der vom Lufi kommt auf dem Turbo wackelt. ok schlauchbandrumm fehlerspeicher wieder gelöschtund gefahren ales ok. doch gestern wieder nach co 900 km davon 750 in einer Tour, Leistungsmangel! Okay, the baseline was read, the regulation limit was not exceeded, and the G62 was found.

Okay, my question is: What else can I do to get the bus running? I'm starting to run out of ideas!

Thank you in advance for your efforts!

Sure, here is the translation of the text from German to English:

"mfb Basti"

This is a German abbreviation that stands for "Mein Freund, das Basti". It is a term of endearment that is used to refer to a close friend or loved one.

Hey, did you check the catalytic converter? It might be clogged!

Hello t3 Surfer;
I've also thought about the cat. However, I can't hear any rattling noises or anything like that, and if it were the cat, wouldn't I have the problem constantly? } Or could it be that the EGR valve is stuck open?

Thank you for your reply!

brg

The catalytic converter doesn't have to rattle! A clogged catalytic converter is characterized by a low air intake volume with a functioning lambda sensor and a very sluggish load response that doesn't reach the target value! If the EGR valve were constantly open, it would also produce excessive soot! You could try sealing it with a metal plate. Try disconnecting or removing the exhaust pipe between the turbocharger and the catalytic converter and take it for a drive! Diesel engines aren't that loud under these conditions. These tests cost you nothing but a little effort!

Now that you mention it, the amount of air being drawn in, according to my KTS (diagnostic tool), is slightly below the expected value. The boost pressure is also increasing slower than what the KTS indicates as the target value, but it does eventually reach the target value at the end. However, I thought that might be due to a delay in the display.
Okay, I'm going to clear the cache now. It's strange that the error only occurs with one driver. And it only happens occasionally. I personally have only experienced the error once, when it happened to him. Yesterday, we were on the track together, and even with the roof installed, he was easily going 160 km/h.

Thank you for the tip!