Ladedruck zu hoch (AFN) | Posts 16+

cksIT wrote:

I've now extended the rod by one rotation, and now it's also adjusting in 3rd gear. In 4th gear, it still isn't adjusting...

Why not give it another try?

because I have to remove the turbo again .


My main concern is that I don't want to cover up another mistake. The pole was still sealed.

If that's okay, then I'll take the turbo out again and turn it 2-3 more rotations. I have to clean the catalytic converter anyway .


I'm going to go for another log ride tomorrow.

Okay, 2-3 is too much. You're already close. I would go with 1-1.5. If the shaft is too long, it will affect the low-end response again.

Are you completely unable to reach him? There has to be a way, right? It's true that your connecting rod might still be sealed. But isn't it the case that the turbo isn't designed for your engine/setup?

I don't see any errors that you could be trying to hide. What exactly do you mean? If you have an original turbocharger and a standard setup, and you shorten the linkage to achieve the desired LD (lambda target), you might be able to mask a problem (e.g., worn spark plugs, clogged catalytic converter).

Okay, since I experienced the problem myself, I know a little bit about it.
The chip tuning increased the boost pressure. Do you know what the value is in millibars?
Here's the translation:

"The problem is that the boost pressure sensor in the engine control unit (ECU) only goes up to a maximum of 2500 mbar, which is 1.5 bar of boost pressure. If the chip is now programmed to 1.5 bar, it enters the range where the LDA sensor is practically at its maximum reading. Consequently, the boost pressure is no longer accurately measured, and it's no longer limited from increasing further."
Therefore, there are modified MAP sensors available up to 3000 mbar. However, the boost pressure map needs to be adjusted accordingly. I also modified mine because I didn't want to compromise on the 1.5 bar boost pressure.

Yes, the chip is programmed for both the turbo and the injectors. That should work.
The pressure sensor is facing upwards, and the rod is underneath it, so it's located between the turbocharger and the engine block. You can touch it, but you can't twist it.

I'm not sure what kind of errors there could be. If the valve were broken, it shouldn't be able to regulate anything at all...

I just can't figure out why he sometimes managed to get the settings right with the old software, and sometimes not.


"I only have a MAP sensor that goes up to 1.5 bar, right?"

"If something is obstructing it, it can't regulate properly... that would explain why it stops regulating around 1.7 bar in chipped mode."

cksIT wrote:

However, the chip is programmed for the turbo and for the injectors. That should work. The pressure sensor is facing upwards, and the strut is underneath it. So, it's located between the turbocharger and the engine block... you can touch it, but you can't twist it. I'm not sure what kind of errors there could be. If the valve were broken, it shouldn't be able to regulate anything at all... I just can't figure out why he sometimes managed to get the settings right with the old software, and sometimes not. "I only have a MAP sensor that goes up to 1.5 bar, right?" if something is obstructing it, it can't regulate properly... that would explain why it stops regulating around 1.7 bar in chipped mode.

That's why it's important to have a log that records the target and actual values. If your display shows 1.7 bar, but the actual value in the control unit isn't being reached, you've practically found the reason.

Yesterday, I finally replaced the turbo.

Result = 0.
It behaves the same way as the previous turbo, or rather, it doesn't engage at all...

The sensor thing makes sense, but it's not really relevant to me right now, because in its unchipped mode, it regulates at 1 bar and goes higher when you give it full throttle (I've seen it go up to 1.35 bar, but it doesn't always do that).
I think that if I can fix this error, I won't have as many problems even in tuned mode (except maybe with the MAP sensor).

Does my theory hold that there simply isn't enough vacuum to retract the rod under full load? Or is the rod always difficult to move, regardless of whether it's under load or not? Because when it's idling, it retracts them properly.



What exactly happens when you disconnect the hose from the turbo? I've been told that the pressure shouldn't increase, and it should be a maximum of 0.4-0.5 bar, or something in that range.
I'm not really understanding this anymore...

cksIT wrote:

So, I replaced the turbo yesterday. Does my theory hold that there simply isn't enough vacuum to retract the rod under full load? Or is the rod always difficult to move, regardless of whether it's under load or not? Because when it's idling, it retracts them properly. What exactly happens when you disconnect the hose from the turbo? I've been told that the pressure shouldn't increase, and it should be a maximum of 0.4-0.5 bar, or something in that range. I'm not really understanding this anymore...

So, it's possible that a vacuum hose is kinked, preventing air from escaping the VTG (Variable Turbine Geometry) control unit quickly enough, which could cause an overboost. Alternatively, the solenoid valve might be damaged.

"If the hose is disconnected, the boost pressure will increase with engine speed. For example, at 4000 RPM, it would be approximately 0.6-0.8 bar."

I don't understand that. I had 1.3 bar.

I need to try it with a different turbocharger again today.

I could try the solenoid valve; maybe it's stuck.

Hey cksIT,

I hope you've reinstalled your 'old charger' and adjusted the rod again! Why don't you do it like HerrAntje suggested, which means adjust the rod another one or two turns and then try it. If you can't write a log right now to see it in black and white, just do that! It should work then!

On the other hand, this should also show you that the turbocharger is slowly creeping into the red zone in the higher gears, where it has more time to react to the exhaust flow. So, with the current configuration, it's working, but it won't give you much more – or significantly more – permanently. It's already operating in a speed range that's right at the edge of the turbocharger's operational limits, especially when you accelerate with full throttle in the higher gears... but so far, it seems to be okay.

Okay, let's try it again, and this time you should get back to me with a satisfied smile!

Something has happened again in the meantime.

"I installed the second charger. It also didn't work initially, but after a 40km drive on the highway, it started working. I was driving around 210 km/h the whole time, sometimes accelerating and sometimes letting the car coast. After that, it could briefly maintain the LD (lane departure) function in 4th and 5th gear (for 1-6 seconds, whenever it felt like it)."

Given that the rod is so easily movable, I wonder: Could it be that the blades are not firmly connected to the rod? Is it possible that the rod can only push, but not pull? This would explain why he can achieve 1.3 bar in 3rd gear even with the hose disconnected...

"Because if the charger is working correctly, it shouldn't be possible, as it wouldn't have any reserve capacity in the higher gears. I was told that it should be around 0.4 bar in 3rd gear, which actually makes sense."


Okay, I'm opening the container today and taking a look inside. Unfortunately, I haven't had time before now... I'll let you know if I find anything new.

cksIT wrote:

Given that the rod is so easily movable, I wonder: Could it be that the blades are not firmly connected to the rod? Is it possible that the rod can only push, but not pull? This would explain why he can achieve 1.3 bar in 3rd gear even with the hose disconnected...

Hello.
The guide vanes are connected to a control ring. There's also a cleaning guide for the VTG somewhere, but I can't find the link right now.
I'm also having issues with the boost pressure right now, and I'd like to know why it's so high.
Best regards,
Dirk

cksIT wrote:

Since the rod was very loose, I have a question: Could it be that the blades are not firmly connected to the rod? Is it possible that the rod can only push, but not pull?

Perhaps you can see here how the blades are "powered".

/viewtopic.php?t=10810,

There's a ring. A VTG rod rotates this ring using a lever. When the ring rotates, the blades move via a similar lever (one lever per blade). If the "levers" are disconnected, it's possible that the entire mechanism stops working. However, based on your description, I find that unlikely. In that case, the blades would probably stop moving altogether.

Okay, I'm still working on cleaning things up because I already have the turbo out.

However, the exhaust pipe won't budge... I've already tried everything with rust remover, let it sit overnight, but even with a hammer, it won't come loose.

Can I simply submerge the entire turbocharger, without the pressure sensor, in a diesel bath? As long as I pour oil into the connection afterward, shouldn't that work?
I'm hoping that the diesel will solve the connection issue...

Furthermore, I suspect the valve again, as I've now experienced a complete system failure for the second time. Suddenly, the pressure dropped to only 0.3 bar. It only recovered after a restart (powering off the valve).

Or could there be another underlying reason for this?

cksIT wrote:

So, I'm still working on cleaning things up, since I already have the turbo out. However, the exhaust pipe won't budge... I've already tried everything with rust remover, let it sit overnight, but even with a hammer, it won't come loose. Can I simply submerge the entire turbocharger, without the pressure regulator, in a diesel bath? As long as I pour oil into the connection afterward, shouldn't everything be fine? I'm hoping that the diesel will solve the connection issue... Furthermore, I suspect the valve again, as I've now experienced a complete system failure for the second time. Suddenly, the pressure dropped to only 0.3 bar. It only recovered after a restart (powering off the valve). Or could there be another reason for that?

"Wasn't that an emergency mode? What does the target/actual value indicate now? If the sensor's measurement range is exceeded, you can adjust whatever you want on the VNT. The sensors are supposed to go up to 2500 mbar (as I understand it), so you can run a maximum boost pressure of 1.3-1.4 bar with such a sensor without constantly hitting the measurement range limit."

Okay, regarding the turbocharger – I assume you're talking about the exhaust side housing? It's a type of interference fit. The safest way to deal with it is to use a plastic hammer and tap it gently all around; eventually, it will move.

No, that wasn't an emergency mode! I've had that enough times already (I still have 0.5 bar in emergency mode).

It had almost no pressure, like when you disconnect the hose from the pressure sensor. At first, I thought it might be the hose, but it was securely connected. After restarting the engine, it worked again...

The desired and actual pressures match, so the problem is not in the control unit (ECU).

So far, I haven't had any success using a hammer... Will I damage anything if I put the turbo directly into the diesel? (Will it damage the internal seals???)