"Misfire" on Touran AZV

Hello,
I drive a Touran manufactured in 2004 with an AZV engine (100 kW, 2.0 TDI PD, no DPF).
Besides several other issues (I had to replace the timing chain at 40,000 km and I'll probably need to replace it again soon, now that I have 160,000 km), this particular problem is currently worrying me.

When accelerating hard for several seconds after the engine has been idle for a while, the engine jerks violently multiple times and then goes into limp mode.
This is often foreshadowed by a louder turbo whistle and reduced acceleration.
During the gear shifting process, you can also hear a loud "WHOOSH" sound, as if a large amount of pressure is being released (this noise has always been faintly present, but it has become louder).
Die Höchstgeschwindigkeit wird nicht erreicht (im Notprogramm sowieso nicht), es fehlen so ca. 15km/h an den 197 lt. Vehicle registration document.
In addition, the consumption seems to have increased (at least I suspect that, as you never really have 100% comparable driving situations).
A friend from the Touran club was kind enough to read the error codes (thanks again, Otti).
1. Turbocharger pressure control: Exceeding regulation limit.
Control unit locked.

He then cleared the error memory, and I drove off, accelerating fully on a long uphill stretch.
It's glitching, the emergency mode is active, and the data in memory remains unchanged.
My mechanic can't find the problem ("Doesn't occur at the moment of inspection" - which is a lie, because I can reproduce the error 100% of the time!), and doesn't seem to be seriously trying to fix it.

Hi,

Quote:

1. Turbocharger pressure control: Exceeding regulation limit

It's nice, but it doesn't say whether the boost pressure is higher or lower than desired.
A whistling sound that's too high-pitched would suggest a simple hole somewhere between the turbocharger and the intake manifold.

Okay, so look for any oily spots and it's best to check the boost pressure while you're driving. Also, please take a look at some of the technical articles on the subject; that's what they're there for.

Best regards, Rainer.

Rainer K. wrote:

Hi, Quote: 1. Turbocharger pressure control: Exceeding regulation limit It's nice, but it doesn't say whether the boost pressure is higher than desired or lower than desired.

So, I understand correctly that the message "rule limit exceeded" doesn't necessarily mean that the pressure was too high, but rather that the control system itself (presumably the PWM of the solenoid valve) is operating at its maximum capacity. My workshop generally says that this error means "overboost."

Quote:

If it were

too small, the whistling sound would fit: a simple hole somewhere between the turbocharger and the intake manifold.

Quote:

The whistling sound is only audible when shifting from full throttle. I've had hissing sounds due to leaky air hoses (in front of the intercooler) before, but it sounds different.

So, first look for any oily spots, and it's best to check the boost pressure while driving. Also, please take a look at the relevant technical articles; that's what they're there for.

Greetings, Rainer}.

Sure, there are quite a few technical articles to read through. My suspicion is that something is stuck in the turbocharger boost control system and only releases after driving for a few kilometers.
I had hoped that someone else had already encountered this exact problem with this engine, but searching for "AZV" didn't yield any useful results.
In a long-term test, one is also more likely to be at a loss.
I guess I'll end up buying a diagnostic adapter after all, even though the €329 price tag definitely stings. Sure, there are cheaper options available, but if I'm going to buy one, I want something decent.
"Okay, this shows what the sensors are measuring. If a sensor is faulty, of course, I'll get incorrect readings."
I'll check tomorrow where I can get a boost pressure gauge installed at a reasonable price.

Hi,

Does the second error (control unit locked) keep recurring?

Best regards,

boki2006 wrote:

Hi, Does the second error (control unit locked) keep recurring? Regards

.

Manchmal ruckelts nur, ohne dass der 2. Error coming.
Most of the time, however, the STG (Sequential Turbine Generator) needs to be shut down, and an AEG (Auxiliary Engine Generator) is required.
(Power off - power on - working again).
It's interesting that the emergency mode can be reset so quickly by briefly turning off the ignition. You can also drive a few kilometers in emergency mode, and nothing resets itself (I read in an article that after some time with the turbo disabled, the error/emergency mode disappeared. However, in my Touran, it only works with a "reset").

As I said, I still don't have a VAG-COM device, and I still don't have a boost pressure gauge.
But this will probably change soon.

For this car, the CAN variant seems like a necessity, I think. It would also allow us to program things like CH, LH, and similar functions.

I would like to briefly add some information about the causes of the errors:
The emergency program was triggered due to excessive boost pressure. This was caused by a malfunctioning boost control system. I have now received a new turbocharger.
The jerking was caused by a fault in the power distribution (PDE) cable harness. Since replacing the cable harness, there has been no more jerking.

However, there's a coolant leak. I had a new cylinder head installed at 60,000 km, and now, at 168,000 km, I need another new cylinder head and a new water pump.

Great, isn't it?

Carsten Kreft wrote:

However, there's again a coolant leak. I had a new cylinder head (ZK) replaced at 60,000 km, and now, at 168,000 km, I need another new cylinder head (ZK) and a new water pump (WaPu). Great, isn't it?

Sure. How does one feel being an unpaid test driver, helping to get the 2.0 TDI engines through the "banana phase" (i.e., when the product is maturing in the customer's hands)?

[Sarcasm ON]
Did you have to sign anything when you placed your order, like...?
"Since our new TDI engine series are not considered fully mature until after at least 4 years of production, frequent defects around the engine are to be expected in my vehicle. These will be repaired under warranty, but do not constitute grounds for cancellation or return... until at least the model year 2010."
[Sarcasm OFF]

ulf wrote:

Yes... how does one feel being an unpaid test driver, helping to get the 2.0 TDIs through the "banana phase" (i.e., when the product is maturing in the customer's hands)?

You feel like you just want to immediately pack Opa's old car with equipment and drive to Wolfsburg, ready to start tearing down the Volkswagen factory right away.

I've driven a Golf I, a Golf II, and a Golf IV, all with at least a quarter of a million kilometers on the odometer. I also have a T4 that will soon exceed 100,000 kilometers without any problems (okay, the relay for the diesel electrics had a cold solder joint).

This Touran has completely disappointed me.

And then, at a trade fair parking lot, I saw a Touran 2.0 TDI parked next to mine, which had been manufactured just two or three weeks later. I asked the gentleman who was getting out of his car how much trouble he'd had with it. His answer: "Trouble? No, nothing to report. I had to take it in for a recall check regarding the dual-mass flywheel, but it wasn't affected."
Me: "You probably don't drive very much, do you?"
He: "I've now driven 150,000 km" (which is roughly how much I've driven by that point).

I turned around, got into my Touran, and silently cried.

Do you still have the error log and can you possibly post it here?

Sebastian@OpenOBD wrote:

Do you still have the error log and can you possibly post it here?

Unfortunately, no.
I still have a general idea of the wording in my mind.

1. Exceeding the regulation limit for boost pressure control.

2. Electrical fault in the pump nozzle injector element.

Oh yes, and as a consequence, the engine control unit will be locked.

The engine control unit is not locking. Try to find or obtain the diagnostic trouble codes, or it may simply need to be replaced. Then we can check the software versions and only then will I start investigating the specific error; unless there's something obvious or known.

Sebastian@OpenOBD wrote:

The engine control unit is not locking. Try to find/obtain the error memory data, or it may simply need to be replaced. Then we can check the software versions, and only then will I start thinking about specific troubleshooting, unless there's something obvious or known.

Okay, I think I've seen the word "locked" used before. But it doesn't really matter, because – what you probably missed – with the new turbo and new wiring harness for a PDE, those errors have now been resolved.

Currently, it's back in the workshop getting a new cylinder head (the second one!), a new swingarm pivot bearing, a new water pump, and some kind of bracket for the front stabilizer bar.

Subsequently, it will become clear whether the sluggish power delivery at low RPM (since the turbocharger change) is still present.

"Yes, there are some people in the forum who have a lot of detailed knowledge, especially regarding charging/injection control systems. I was actually planning to buy a diagnostic adapter myself. However, the price of €349 and my lack of experience in interpreting the measured values are currently holding me back."
Perhaps there's a reader out there with the necessary hardware and experience that I could visit?
Okay, hier ist die Übersetzung:

"Could you please translate the following text from German to English? (Please provide only the translation, no explanations.) Or, could you recommend a suitable workshop in the northern Sauerland region and surrounding areas?"