TDI 1.9 AVF Turbo Problems & Solutions

Hello,

The turbocharger in my VW Passat TDI was replaced, and unfortunately, there have been problems since then.
On the first trip, after 25 km at a speed of 150 km/h on the highway, the pressure hose connecting to/from the intercooler detached from the plastic pressure pipe (on the right side, above, when standing in front of the car), and there was a lot of smoke. In the emergency mode (?), it returned to the workshop.

After the hose connection was repaired, the problems really started: first, the car had very poor acceleration (with jerks), especially in the lower RPM ranges (even with full throttle), and above 120-130 km/h, it had little to no power, or it felt like someone was constantly pressing the brakes.

After 4 agonizing days with a disabled TDI, the mass airflow sensor (MAF) and the magnetic valve were replaced one after another. The MAF sensor was definitely okay.
After replacing the solenoid valve, the car ran like new for about 80 km. However, after I left it parked for 2 hours, the joy was over. It had VERY LITTLE POWER (like before, but the fluctuations during acceleration were gone). After another three days, the TDI suddenly started running 'almost' normally again this morning. However, at speeds of approximately 120-180 km/h in 5th and 6th gear, the engine feels sluggish and accelerates slowly, and sometimes makes a strange noise.

'Recently (?), when the engine is idling (e.g., shortly after starting or when in neutral), I've noticed a constantly repeating and relatively loud squeaking noise that seems to be coming from the EGR valve housing. I've never noticed it before (!), but the workshop says it's normal.'

The problem is that the car simply doesn't run the same way it used to! (approximately 90,000 km) And I'm worried that it might not work properly again tomorrow!

Of course, the error memory had no entries... and I think the mechanics at the workshop are starting to look at me strangely, because they can't understand the loss of power (but I, having driven the car for 2 years, know that if there's no power at all when going uphill in 5th gear at 2200 RPM and 100 km/h with 130 horsepower, even with the accelerator pedal fully pressed, something must be wrong).

I also can't say for sure whether the problem existed before the hose burst, or if it's related to the new turbo, because I was already moving very slowly that day due to heavy traffic, and the hose failed when I first gave it full throttle.

PLEASE, CAN ANYONE HELP OR HAVE ANY IDEAS?? I'M REALLY IN A BIND!!




Update August 20, 2023.
The fear became a reality today. After a short stop at the rest area on the highway, the car suddenly lost almost all power when accelerating in all gears.

How long have you been driving without a pressure hose?

Assuming everything else is fine according to your assessment, I would suspect a faulty turbocharger.

'It spun endlessly without the pressure hose! Furthermore, the motor could have sucked in all sorts of unfiltered things during that ride without the pressure hose!'

It's best to have a boost pressure measurement performed.

Regards,

Manuel.

It was about 3-4 kilometers until I got off the highway.

The emergency service had temporarily patched up the hose, and I carefully drove to the workshop.

The head of quality control at VW today denied that the turbocharger could have been damaged in any way by the hose defect. 'That would not be possible,' he stated.

'Since the problem doesn't occur constantly, and the alleged 'error' cannot be 'reproduced,' I was rather rudely informed today that they no longer want to do anything about the car...'

TO PUT IT SIMPLY: I HAVE A BIRD, BUT I'M JUST IMAGINING IT.

I'm at a loss for words...

Why was the charger replaced? What was wrong with it?

due to oil leakage at the pressure hose connection...
The VW technician said it was coming from the TURBOCHARGER.
Meanwhile, I've discovered that this probably isn't the case! Too late...

It was about 3-4km until I got off the highway.

The emergency service had temporarily patched up the hose, and I carefully drove to the workshop.

The head of quality control at VW today denied that the turbocharger could have been damaged in any way by the hose defect. 'That would not be possible,' he stated.

TO PUT IT SIMPLY: I HAVE A BIRD, BUT I'M JUST IMAGINING IT.

I'm at a loss for words...

You've got a clever workshop master there!

If the pressure hose is disconnected, the compressor naturally loses the generated boost pressure. This boost pressure normally slows down the compressor. If this counter-pressure is absent, the compressor will reach speeds for which it is not designed!

Nothing may have happened, but it could have!

Consult a lawyer! You have all the documentation, right?

I wouldn't let that happen!

Regards,

Manuel.

Lawyer?

I was immediately told that the hose defect had nothing to do with the turbocharger replacement. 'As you can see, it's on the right side, and the turbo is on the other side.'

How am I supposed to prove the opposite...?

By the way, Volkswagen paid for the turbocharger as a goodwill gesture. Only the labor costs were due.

To be honest, I don't believe in coincidences like that. On the very day the loader was replaced, the hose connection burst. It's supposed to happen sometimes, especially since these things are held together with that strange clamp. Still, it's a strange coincidence.

Is there a contact point in Wolfsburg that I can reach out to?

'You've got quite the clever workshop master there!'

-No comment- otherwise, I really need a lawyer...


Could anything else have been damaged besides the turbocharger?
Can anyone identify the sound coming from the AGR valve?

Lawyer?

I was immediately told that the hose defect had nothing to do with the turbocharger replacement. 'You can see, it's on the right side, and the turbo is on the other side.'

How am I supposed to prove the opposite...?



I'm sorry, I understood that the pressure hose detached from the compressor!

Oh, if only the hose burst, then nothing major happened because there's still enough residual pressure in the system!


By the way, Volkswagen paid for the turbocharger as a goodwill gesture. Only the labor costs were due.


What did you have to pay?


Is there a specific contact point in Wolfsburg that I can reach out to?


Tel: 0800 / VOLKSWAGEN


'You've got a clever workshop foreman there!'

-No comment- otherwise, I really need a lawyer...


What do you mean by that?


Can anyone identify the sound coming from the AGR valve?


If that's the kind of rattling noise, then it might be normal for a DPF (Diesel Particulate Filter). You could try temporarily disabling the AGR (Abgasrückführung - Exhaust Gas Recirculation) to see if it makes a difference.

Regards,

Manuel.

Finding a lawyer is easy. What's more difficult is finding a competent expert in this field. But this cannot continue!
There are also institutions similar to mediation centers at the chambers of crafts.

FriscoTom wrote:

I was immediately told that the hose defect had nothing to do with the turbocharger replacement. "

You can see, it's on the right side, and the turbo is on the other side."

Quote:

Hi. This is yet another new level of selling something to customers while insulting their intelligence – with a quality similar to "a short circuit in the bedroom can't have anything to do with the blown fuse in the basement. You see, they're on different floors!"

How am I supposed to prove the opposite...

By first explaining to them the structure of the charging system (since following the broken pipe against the flow of liquid will inevitably lead to the charger), or, if necessary, by instructing the specialists to repeat the explanation in front of an arbitration panel, the automotive trade association, or other "popular" institutions.

I think it's time to open another section here featuring the funniest workshop-related quotes }.

The head of quality control at VW today denied that the turbocharger could have been damaged in any way by the hose defect. 'That would not be possible,' he stated.

'Since the problem doesn't occur constantly, and the alleged 'error' cannot be 'reproduced,' I was rather rudely told today that they no longer want to do anything about the car...'

TO PUT IT SIMPLY: I HAVE A BIRD, BUT I'M JUST IMAGINING IT.


That's typical Volkswagen behavior. When they don't know what else to do or don't want to admit their mistake, they become rude, unprofessional, and ridiculous! I've also experienced two similar cases of shoddy workmanship. In one case, mentioning that I would immediately contact a lawyer through my legal insurance helped. In the other case, it didn't achieve anything, as the mechanic was potentially incompetent and the dealership manager was mentally deficient. However, these incompetent people also didn't get paid for their work!

The local chamber of crafts should be a good starting point! If that doesn't help, then contact Volkswagen customer service. Experiences from friends suggest that things usually get resolved then.