Turbo Control 1.9 TDI 130HP - 200k Miles

Hello fellow DIY enthusiasts,

I have now owned an ASZ engine for approximately 10,000 km and have the VCDS software and hardware from Kaufmann . I am experiencing the following issue with my turbocharger pressure control, as you can see in the log file: large overshoots, with a deviation of up to 0.5-0.6 bar. Furthermore, the control system seems relatively slow. This is my "first" log file that I have created, and I hope that this information can be helpful.
I've already read a bit about VTG in the forum, but I still wanted to hear your opinions regarding my specific problem. What are your concerns when you see the curves?

Regarding the log entry at 14:05: How can the boost pressure increase while the engine speed is decreasing, especially to that value?

Just a quick note: About 3000 km ago, I removed the intake manifold, exhaust manifold, etc., and also cleaned the turbocharger, specifically making sure the variable geometry turbine (VTG) moved freely and checking for wear. The turbocharger shaft has only minimal play, maybe three to four tenths of a millimeter. I installed new gaskets, etc., and deactivated the EGR valve. I didn't change anything on the VTG linkage hub. I personally would rule out a stuck VTG, as I cleaned and removed soot and rust, etc.

Thank you very much for the helpful answers!

Hello,

The logging is not really optimal; see the technical article on logging for more details.
However, as you scroll down, it becomes clear that the actual boost pressure doesn't really follow the target boost pressure very well.

Either the solenoid valve (block, N75) for the variable turbine geometry (VTG) is faulty, or the turbocharger is seizing up when it gets hot. The latter is not uncommon; everything looks fine when the turbocharger is cold, but when it gets hot, it starts to malfunction.

I would first check the vacuum system for leaks and, if possible, replace the solenoid valve block with a known working one.
If the behavior remains the same, it's probably the charger.

Best regards, Rainer.

I'm experiencing a similar problem on stage with my daughter's A3 8L with an ASZ engine. First, I'll remove the tuning box and seal the oily connections in the intercooler system with new seals, then I'll check for leaks. I'll also check the vacuum system for leaks and, if necessary, replace all the 3mm hoses. When you don't have any work, you buy some parts.

Hello.

I've found a solution that worked for me with a similar problem, and it might also work for your engine:

/viewtopic.php?t=30858

Post by Alevuz (November 23, 2020, 10:13) with the YouTube video link...

SG
Manfred.