Turbo Failure: What to Do?:-((

Fortunately, I haven't had anything to contribute to your survey about faulty turbos yet. However, mine failed on Saturday. It has 97,000 km on it, and has had a Wetterau chip installed for about 10,000 km.
'Recently, I've been experiencing a recurring issue where the car goes into limp mode. Initially, it only happened when accelerating fully, around 3000 RPM. The usual error message is 'Boost pressure regulation difference...'. However, lately, it's also been happening when driving normally or during light acceleration. I've always wanted to check the VTG (Variable Turbine Geometry) system, but I haven't managed to do it yet.'
Well, and on Saturday, he did it again, while driving normally. So, the usual thing: ignition off, ignition on. Then everything was fine again. And after that, I wanted to give him a bit of a run. So, 3rd gear and accelerating up to 4000 RPM. Afterwards, there was a lack of power and he was smoking like a Formula 1 Mercedes .
I removed the turbo today. The shaft was broken, and the impeller blades of the compressor wheel had failed. However, the variable turbine geometry (VTG) was running very smoothly. I was able to test it without any problems now...
What do you think, did the VTG (variable turbine geometry) get stuck, and is the turbocharger over-revving, or did the shaft just break?

To determine that, you would have needed to monitor your boost pressure.
Normally, it switches to emergency mode if the pressure reaches approximately 1.5 bar and remains at that level for 2 seconds.

I don't know how the emergency shutdown works in case of low pressure.
I still think you must have had a very bad experience.
Either due to a technical defect or through hacking/modifying.
"If there had been a load pressure display, a serious accident could have been prevented."

'I've also had the boost pressure gauge lying around for a while now... But now it will be installed at the same time as the new turbocharger. I also want to find out what's causing the limp mode. But maybe installing the new turbocharger will fix that problem.'

Is the loader the only thing you need to repair? Just because you wrote 'the bucket wheels of the compactor wheel have failed,' does that mean the individual components of your loader are also okay?

It seems like all the debris has accumulated in the intercooler... That's where the larger particles usually get stuck. So, I don't think anything made it through to the engine. Let's fix it first, and then see if it runs normally again.

Hello schroederliese,

"I experienced exactly the same issue (Passat with ATJ engine, chipped to 150 hp), but at approximately 160,000 km. There were the same warning signs (increasingly frequent limp mode, initially only under full load, then also during normal operation). In my case as well, the turbocharger shaft broke under full load (3rd gear, 4000 rpm). This resulted in a significant amount of aluminum debris from the compressor wheel being scattered throughout the intake system. Most of it was caught by the intercooler, but only very small aluminum particles made it into the engine."

I only replaced the charger and have driven 10,000 km since then without any problems.

I believe the problem originated with the VTG (Variable Turbine Geometry). Because with the new turbocharger, the car ran much more smoothly and harmoniously across the entire RPM range, and it hasn't experienced any more limp modes since then.


Greetings.

Rupert.


PS: Before you restart it, check the oil level! In my case, after about 20 seconds of engine running with a broken turbocharger shaft, almost 3 liters of oil were missing.

Hi Rupert,

Well, I guess that's not an isolated incident... Yours just lasted a little longer.
'Yeah, I already noticed something about the oil. I checked right away when it started smoking. At first, I thought the head gasket might have blown, that's why there was smoke. But there wasn't any water missing...'
'So, I pulled out the dipstick, and sure enough, there was nothing left on it. And when we removed the lines and the low-level coolant reservoir, we found a significant amount of oil... I think there was about 1 liter of oil in the low-level coolant reservoir alone...'
But an oil change is due again anyway .
Okay, let's hope the turbos last longer this time.

What were your loading speeds with the chip?

CU Gremlin.

I can't say for sure, as I haven't had a boost pressure gauge installed until now. I'll let you know when it's running again...

Okay, so...
The car is running again, and the boost pressure gauge is also installed.
It produces approximately 1.3 bar of boost pressure when accelerating fully. Of course, this could be unhealthy in the long run...
Okay, I was just bored and decided to disconnect the vacuum hose from the VTG (Variable Turbine Geometry) adjustment.
It is now intermittently entering a limp mode with the error 'Intermittent boost pressure regulation difference.'
So, it can't be due to excessive boost pressure, as it was running at less than 0.5 bar. Does the engine control unit also trigger the error code when the boost pressure is too low?

Yes!

My turbo has 180,000 km on it, of which approximately 140,000 km were driven with a chip tuning modification. Unfortunately, I don't know the exact boost pressure, but it is definitely increased.

Best regards,
Uwe

The error "boost pressure regulation limit exceeded" appears when you stay below the target boost pressure for too long.

@Rupert
If the engine is pumping all the oil through the turbo bearing, wouldn't the oil pressure light come on after a short time?

Regards,
Olaf.

Hello everyone,

Sorry for the delayed response, but I haven't been active on the forum for a while.

@gremlin:
Unfortunately, I don't have a boost pressure gauge, so I can't specify the exact pressure. The boost pressure is, of course, higher than stock, but according to the programmer, it's within the tolerances allowed by the manufacturer, i.e., at the upper limit.
tcm vehicle technology.
I believe the problem was with the VTG (Variable Torque Gear), as the car would sometimes accelerate extremely well and then suddenly revert to a limp mode. Could it be that the pressure spikes occurring here couldn't be dissipated quickly enough?

@olaf:
"If that much oil is missing, the oil pressure warning light will definitely come on. However, I didn't notice it in that situation (Friday afternoon during rush hour), and I ended up turning off the engine relatively soon anyway."

Greetings.

Rupert.

karlstein12 wrote:

The boost pressure is naturally higher than the standard setting, but according to the programmer's statement, it is within the tolerances allowed by the manufacturer, i.e., at the upper limit.

Here's an example:

The ASZ engine in the Polo has a KP 39 turbocharger manufactured by KKK.

According to the website (Borg-Warner), this series is designed for engine power outputs up to 100 kW and mass flow rates up to 0.14 kg/sec.

The untuned air-standard Zündmaschine (ASZ) produces, according to the LMM value, approximately 950 mg per cycle at its maximum pressure (Pmax), which results in a mass flow rate of 0.127 kg/sec.

In terms of performance, the loader only has about 4% of its capacity unused; while the mass flow seems to have nearly 10% of unused capacity, there may be uncertainties to consider, such as flushing losses, which also affect the loader's performance.

This design, which uses chargers with the lowest possible reserve capacity, aims to achieve the highest possible pressure build-up even at low engine speeds.

My guess is:
If a tuner has increased the boost pressure in a newer car, the new value might be "at the upper limit" - but which side of the limit (i.e., still below it or already above it ), is something everyone can imagine for themselves...

Hello schroederliese and Karlstein12,
My turbocharger also failed yesterday.
I drove approximately 30 kilometers on the train, using the full capacity.
After that, I let it idle for about 3 minutes to cool down, and then another 3 minutes with the engine off before turning it off completely.
Later, I quickly drove out to get something, and wouldn't you know it.
It produced a lot of smoke, like a Formula 1 Mercedes. In addition, there was a metallic clattering sound.
Boost pressure was zero. Consequently, there was no power output.
Oil was now also coming out of the exhaust pipe.
I went to the mechanic, and he immediately diagnosed a turbocharger failure.
Since my car only has 53,000 km on the odometer and is only 2.5 years old, the turbocharger will be replaced free of charge under warranty. However, I have to pay for the labor costs.

Best regards, Jürgen.

w123diesel wrote:

Yesterday, the turbocharger also failed on my car.

Hi Jürgen,

Which vehicle model? Engine code? Tuned or stock?
That would significantly increase the informational value of your answer .