VTG: Workshop Findings & Technical Details | Posts 16+

According to the workshop, it's a VTG!

Today, something else was found: The charge air hose from the turbocharger (the main hose) was not properly connected. However, this was not the solution to the problem. Again, the car went into limp mode, and the same errors appeared as described above!

Okay, here's the translation:

'In summary:'

N75 replaced.
Hoses checked.
LMM changed.

no solution!

Who has advice?
Is it actually the turbocharger itself that's causing the problem, and is it happening only intermittently?

Hawkeye.

Hi.

Check the error database, specifically under "stuck VTG" or similar entries.

If what is described there doesn't help, a remote diagnosis will be difficult. Unless you decide to have a new charger installed "just in case."

It's also conceivable that the boost pressure sensor is malfunctioning intermittently, while the turbocharger itself is fine .

Apparently, the bug has been found!

The difference in boost pressure was triggered by a bypass valve. This valve occasionally jammed and has now been replaced. (located at the bottom, near the turbocharger).

Since then, there have been no more emergency shutdowns!
Hopefully, it stays that way!

Thank you very much again.
Hawkeye.

Hello,

"Hmm, bypass valve? So it was probably a turbocharger with a wastegate, not one with a variable geometry turbine (VTG). Most forum users probably don't want to spend the time and effort to "look into a crystal ball" when answering questions."
Therefore, I request accurate descriptions of errors and engine problems. Guessing games are unnecessary and don't help anyone.

Best regards, Rainer.

Hello Rainer!
I'm sorry, but as a non-expert, I only have the information I received from my workshop. Sometimes, I suspect they tell me things that aren't entirely accurate! When I asked if it was a VTG or a wastegate, I was told it's a VTG turbocharger.

After the repair, it was determined that a faulty bypass valve was the cause.
After initially replacing the supposedly faulty N75 valve and the mass airflow sensor (MAF), and after a third visit where it was clearly determined that the charge air hose was loose, this was identified as the only possible source of the problem.
Well, they made a good profit off my car!

It seems it was that bypass valve all along!
Sure, no problem!
Hawkeye.

Okay.

Hello,

Do you have the part number for that mysterious "bypass valve"?

I'm also very interested in what this bypass valve does and where it's located.

Denn deine Problemchen habe ich leider auch, da ein Freund von mir einen intakten 1 Z hat, habe ich mir immer die Teile bei ihm ausgeliehen, getestet und wieder zurück getauscht. Hat aber nie zum Erfolg geführt. LMM, Relay 109.

'The solenoid valve was making a terrible ticking noise, just like it did for many others here. I replaced it, but that didn't solve the problem. So, it probably isn't related to the power loss I'm experiencing around 3,600 RPM in 5th or 4th gear. However, now it's harder to start, and I have 2 new error codes!'

Control unit defective, error code 65535.
Fuel shut-off valve N109 - Intermittent fault/Short circuit to ground/Sporadic/Error code 01237 031.

The last issue doesn't seem to be related to the solenoid valve. There's a strange buzzing sound, and sometimes it comes from the engine block when the ignition is on, somewhere behind where the power module is plugged in. It's hard to describe. Maybe someone can tell me what might need to be replaced? Or do I need to take it to a VW dealer?
The best thing to do would be to just get a new car. But I can't sell this one in its current condition.

Also daher würde ich gerne dieses Bypassventil von meinem Kumpel mal wieder ausleihen. Wäre nett wenn du mir eine genaue Lagebeschreibung des Teils machen könntest. Oder NR. dann gehe ich zu VW. SpUnfortunately, I cannot provide a translation for the word 'rengansicht' as it does not appear to be a recognized word in German. It is possible that it is a misspelling, a regional term, or a made-up word. If you can provide more context or clarify the intended meaning, I may be able to offer a more accurate translation.

Thank you very much.

Hello,

Be careful that we don't mix up all our mistakes here.

Error number 65535:
Your control unit has detected an internal error. Unfortunately, in most cases, the only solution is to replace it.

Error 1237.
If the shut-off valve is not functioning correctly, it can interrupt the fuel supply during operation, causing the engine to stop immediately.
You can replace this valve, but if the problem occurs intermittently, like in your case, I would first check the wiring.

Sorry, I didn't want to confuse things. I just wanted to add something.

It would be important to know the part number of that bypass valve. VW doesn't want to spend any money on it. Those guys are already making enough money as it is. And troubleshooting can be expensive.

Hello,

Before you start replacing everything, you might want to consider doing something else first.
Let's investigate the issue with the shut-off valve. This is likely the more probable cause of the jerking or stalling you're experiencing.

I will find out the number.

Hawkeye.

Hi Michael,

After real defects in the engine computer are very rare, based on general forum experience, I was reminded again of a possible explanation for the error: a faulty relay 109, which can cause arbitrary nonsensical entries in the error memory.

What do you think about this possibility?

Hello Ulf,

I had also considered that. However, in that case, the issue would be intermittent rather than permanent. Furthermore, a problem with pin 109 can cause a variety of very vague error messages (and the error code 65535 is usually not among them).

Report:

Okay, the workshop told me the following:

Valve number: 1J0906283C.
Magnetic valve between the intake manifold and the intake hose.
It has two electrical connections!

According to the service manual, this valve can occasionally fail intermittently.

Hawkeye.

I inquired with VW, and the replaced part at Hakeye is the electric switching valve, which was causing the ticking sound in my car when the ignition was on. But that part is already new!

My friend, who also has a 1Z, is going to install the control unit this weekend. If the tax identification number is the same.

If the engine still isn't running properly, I guess I'll have to take it to VW.

Or, does anyone perhaps have any other ideas about what I could do?