Golf 3 AHU - Problems with Turbocharger Pressure Control

A few weeks ago, the engine started making a 'whistling' sound while running under load; it sounded somewhat like a pressure relief valve.
That noise is gone; however, the following effect is now occurring: When the engine is under load and running at full throttle, the power suddenly cuts out. After restarting, everything works again.
Error code:

Address 01 -------------------------------------------------------
Controller: 028 906 021 GG
Component: 1.9L R4 EDC 00SG 1443
Coding: 00002
Shop #: WSC 01319
1 Fault Found:
00575 - Intake Manifold Pressure
17-00 - Control Difference
Readiness: Not applicable.

I have already checked all the pressure hoses. Where else can I look?

Best regards,
Holger

Hi Holger,

I would like to draw your attention to forum rules 2 and 3.
Okay, I'm ready. Please provide the German text you want me to translate.

You clearly didn't search for anything.
"00575" provides a lot of tips, and the title is almost a quote of the _undesired_ version .

Please first review the search results – you can use the 1Z model as a reference as well, since it's almost completely identical.

m;

I've searched, but I've found very little information about AHU. For the combination 00575 and 17-00, I only found ONE (not very informative) entry. But if the 1Z is the same... I'll search again.

Despite everything, I am grateful for any advice. Unfortunately, I'm 'just' an electrician; I could also even the score if it comes to engine control units and that kind of stuff .

The log file from the test drive is located here.
Perhaps someone will eventually be able to use this data (approximately 3 km of highway, the interruption occurred shortly before the end of the log).

Hmm, I think we've both made the same mistake. My Golf 3 TDI, 1.9 liter, 1Z engine.
It doesn't want to go any faster than 140 to 160 km/h, and it goes into emergency mode.
I think I've already replaced everything that needed to be replaced.
new LMM (mass airflow sensor), new turbo plus, dose control valve, etc., etc., etc., and new intercooler piping.
Okay, everything's fine. I don't know what to do next either.
and think that you should try doing the same thing first.
greetings to Chris from Stuttgart.

@ Holger

GRRR - you should have mentioned the chip.

Please don't let this turn into one of those threads where we all rack our brains and then eventually figure out that the car has been modified for years.

Chip is okay, but please mention it. Is 112 horsepower an *** model?

Perhaps your boost pressure sensor in the engine control unit (ECU) is defective - comparing the pressure readings with a separate LDA (Load Dump Analyzer) will provide clarity.

m

hi martin
I've thought about that too.
because everything except the control unit has been replaced.
You can find a new and good one at an auction house for 50 to 60 euros.
Best regards, Chris.

Okay, if things are bad, then there's nothing good.

because you first have to pair the new key with your system.

Why are there always these wild trading frenzies?

Then I would have simply exchanged the entire car.

You can always use a boost pressure gauge, and it will tell you whether the engine control unit (ECU) is actually defective.

You can also test each sensor individually.

m;

So, the chip is from ******** Tuning, and it was tested on a Bosch dynamometer, which showed 112 horsepower. It didn't quite reach the promised 118 horsepower. I, however, saved quite a bit thanks to a dealer discount...
Self-soldered approximately 150,000 km ago, it definitely provided more power without increased fuel consumption, especially in the lower RPM range (which was important to me). Along with a new suspension and 205 tires, it's a top combination, but it's limited to 190 .

The chip is probably not the problem, as the error only started occurring sporadically about 3000 km ago (whistling sound).

Okay, I'm going to check the control valve and the pressure sensor on the turbocharger now. I'll get back to you later.

Oh yes - one more thing: The fuel consumption has also increased. It's about 9.5 liters per 100 kilometers when driving on the highway at 180 km/h, otherwise it's about 7.5 liters. He didn't have that before either.
It probably isn't due to the mass airflow sensor (MAF), as it's only 10,000 km old.

Best regards,
Holger

AAAAHHHH

Quote:

It probably isn't the mass airflow sensor either; it's only 10,000 km old...

How can one determine the function based on age?

Then children would never get sick!

The LMM (likely referring to a laser module or similar device) is only considered acceptable if it has been measured (or if a diode or another LMM showed no change).

Please proceed in a more systematic manner .

m;

@dagobert:

If I understand you correctly, you've been driving around with this chip installed for 150,000 kilometers, right? What is the total mileage of the engine then?

I believe that the whistling noise indicated the impending failure of the turbocharger, which is under greater stress due to the modifications (e.g., increased boost pressure via a chip) and has now reached its wear limit. This manifests as insufficient pressure build-up, which, during prolonged periods of aggressive driving, leads to such a significant deviation from the intended boost pressure that the engine control unit logs an error and enters a limp mode.

As far as my theory goes regarding your problem.

Regards,
Alex.

@Dieselmartin

The LMM (likely referring to a mass airflow sensor) was re-tested by an external VAG workshop because it was still under warranty. The engine now has 260,000 km (approximately 160,000 miles) on it, and there is no significant oil consumption.
The increase in boost pressure was only minimal.

I've also had the thought that the turbocharger might be worn out.
Sure, here are the translations:

**Question 1:**

'Please translate the following text from German to English. Provide only the translation, without any explanations.'

**Question 2:**

'Please translate the following text from German to English. Provide only the translation, without any explanations.'
Can I use the turbocharger from a 1Z engine without modification in an AHU engine?
2. Can I install a turbocharger designed for an Audi AHU engine into a VW?

@Dieselmartin

We could give each other a call sometime, if you like. Such misunderstandings can be avoided in conversation . My friend is currently training to become a certified automotive technician, but unfortunately, he will be under constant stress for the next 3 weeks .

dieselmartin wrote:

AAAAHHHH Quote: It probably isn't the mass airflow sensor either; it's only 10,000 km old... How can one determine the function based on age? Then children would never get sick!

While this "logic" is a bit of a stretch, it's still good...

I've probably found the problem. The boost pressure valve is intermittently failing when powered with 12V. It doesn't respond every time, but roughly every other or third time. Whatever the reason...
I'm going to change it.

Best regards,
Holger

'Addendum: Error corrected.' It WAS the solenoid valve!

Thank you for the feedback!

It's a shame that this isn't done more often by the people who are asking the questions.

Best regards, Rainer.