Turbocharger Error: Boost Control Issue

Hello everyone, what could be the cause of the error message "Boost pressure regulation"?


It's a VW Golf Mk4 Estate (Variant) with a TDI engine, and the engine code is ASZ.

It goes into limp mode when accelerating fully in 4th gear at 4000 RPM.

The mechanic at the said that a new turbo is needed.


Are there any other potential sources of error?



Best regards, Patrick.

Try tapping the hanging VTG loading adjustment.

The error message is likely.
Boost pressure exceeds limit.
Boost pressure below the defined limit.

If it's not smoking excessively and making any noises (like loud whistling or screeching), I wouldn't completely panic just yet.

"I've experienced this problem before with my Octavia (81 kW)."
The error disappears when the ignition is turned off.
Okay, if it happens again, quickly disengage the clutch, turn off the ignition, and then turn it back on; it will probably work again afterward (but usually only for a short time).
"The only thing that helps is to check the VTG linkage for proper operation (possibly using a VAG Com to perform a diagnostic test and observe the VTG pressure sensor). If that doesn't help, check and verschandeln the VTG adjustment mechanism of the turbocharger."
I think there's probably a technical article about it.

Try it first.

I just spent a little more time underneath my car.


The VTG is now moving again after I pulled on it firmly and it came loose.
After that, there was a slight creaking sound, which stopped after about 20 movements.



After that, I took it for a test drive, and what can I say?


He still goes into limp mode if you shift him directly to the track from second gear.

The emergency brake engages at 4000 RPM in the fourth gear.

And now?????????????????????????????????

Disassemble and thoroughly clean .

How easily or with what difficulty can the VTG be moved manually?

I was lying under the car and had to wear gloves to protect my fingers.
(No, I'm not a softie, but a mechanic working on railway cars.)

Lolohopper wrote:

How difficult or heavy is it to move the VGT manually?

It's easy at first, but then it becomes increasingly difficult against a stiff membrane spring. At the end of the ~1 cm stroke, you almost need pliers and the pain tolerance of a fakir...

My tip:
Run the "actuator diagnostic" for the "boost pressure control valve" several times using VAGCOM (it will switch off after 30 seconds), or keep the basic setting in module byte 11 active for several minutes at a time, both while the engine is idling.
It repeatedly opens and closes the valve train (VTG) with maximum force, essentially working it back and forth. With a bit of luck, this temporarily resolves the problem.

The only somewhat annoying thing is the slow 10-second cycle time of the default setting (but this can be accelerated via chip tuning ).

I used to have an ASV (with a 110 hp engine) that also had a scratching, almost jamming variable transmission gearbox (VTG).

After driving it hard and even flooring it on the road for a few kilometers, the thing suddenly started running smoothly.

It's worth a try before you disassemble it.

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

Check out my response from today to drewsho. (Error 575, intake manifold pressure control differential). I had this issue on the 1Z before, but maybe it will help you.

Best regards,
Herbert.