Bin langsam am verzweifeln, Fehler 0575 Regeldifferenz | Posts 32+

Malte1408 wrote:

Then there's still the question of whether anything has been done to the software, or specifically, the characteristic maps within the MSG. As I said, nothing changes on its own.

Sieht mir eher nicht so aus: zumindest in einem der Logs läuft das LD-TV bei zuwenig Druck immer entlang der Korridorwand für max. Dreconstruction.

Is the VTG rod still sealed with its original protective coating, or could it have been rotated too far?
EDIT: I just saw the phone photo again, so it's probably still the "factory" setting.

I would still try shortening them gradually (starting with one rotation less): I think it can only get better from there.

Hi Ulf,

"The rod and the paint definitely haven't been touched by me. You can see that very clearly in the first of the three pictures. I also still have a warranty on the turbocharger, so I don't really want to mess around with it. I'm honestly completely clueless. I've now replaced some of the vacuum hoses. But it shouldn't be the vacuum hose causing the problem, because the VGT (Variable Geometry Turbo) is fully engaged even when the valve is bypassed. And that's the same vacuum source. Is it possible to compare the adjustment of the VGT rod between different turbochargers? If so, someone could take a picture of their VGT rod. That would at least indicate whether it's the same type of turbocharger."

Are you absolutely sure that the TV setting on my control unit is correct? When requesting pressure, the TV doesn't even come close to reaching 30%.

Can this be configured in the Outlook settings (MSG), and if so, where and how?

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Is it possible to compare the settings of the VTG rod from one loader to another?

No, quite the opposite. The VTG (Variable Turbine Geometry) is adjusted on the test bench to achieve minimum and maximum flow rates. One of the reasons why many maintenance companies don't have this capability is also why Honeywell Garrett has withdrawn approval for them to repair these turbochargers (see bulletin).

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because with a bypassed valve, the entire VGT goes in.

"Fully engaged and staying there requires less negative pressure than constantly going back and forth."

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Are you absolutely sure that the TV of my control unit is working correctly? When requesting pressure, the TV doesn't even come close to reaching 30%.

Hmm, yes, that's probably normal at high RPMs. It should go down to around 24% when idling.

However, even at 35%, the torque should be sufficient to build up load dynamically above 2000 RPM, as the VTG (Variable Turbine Geometry) needs to open occasionally. Otherwise, it could be eliminated altogether.
I mean that about 60% would be considered normal.

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Can this be configured in the MSG, and if so, where and how?

No, in this case, it can only be done by modifying the identification fields, which means reflashing the EEPROM. I'm not sure if it's even necessary to physically remove the EEPROM from this older part. -> Chip tuning.


Did the workshop that fixed the excessive boost pressure without replacing any parts perhaps install some kind of restrictor or other nonsense in the vacuum line to the VTG (Variable Turbine Geometry)? Is the N75 valve still the original one that belongs there? Could it have been replaced with a wrong one from another vehicle? (But I think they probably just adjusted something.)

I would now test-exchange the N75, and please use a voltmeter to measure the voltage at the connector of the N75 during actuator diagnosis or basic setting MWB 11.

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Is the VTG rod still sealed with its original protective coating, or could it be turned too far? EDIT: I just saw the phone photo again, so it's probably still the "factory" setting.

Yes, but even the factory setting could be wrong. In my opinion, even if it's fully tightened, it might still cause thread damage (LD). This could also mean that the rod is too long and that thread damage (LD) can only be created by excessive tightening, which wouldn't happen in normal operation.

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Are you absolutely sure that the TV of my control unit is working correctly? When requesting pressure, the TV doesn't even come close to reaching 30%.

At least in the one log file I checked, the TV (total volume) trend for patients with LD (low density) corresponds to the software's specifications.

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I would now, in any case, replace the N75 for testing purposes.

And please take a voltmeter and measure the voltage at the connector of the N75 during actuator diagnosis or basic setting MWB 11.

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Absolutely correct! "@drewsho: You should be able to measure a voltage of Ubatt multiplied by the duty cycle using an analog multimeter, so approximately 14 volts when VTG is ON." If the voltage drops by more than 1 volt compared to the battery voltage, there's likely a copper corrosion issue somewhere that could explain the LD deficiency.

Yes, but even the factory setting could be wrong. In my opinion, even if it's fully tightened, it might still cause premature wear. This could also mean that the rod is too long and only generates premature wear through excessive tightening, which wouldn't happen in normal operation.

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Therefore, my suggestion is to shorten the shaft – at the latest when the clamping force on N75 is okay, and if replacing it doesn't help either.

The only thing that comes to mind is that a similar phenomenon occurred about 5 years ago with the old loader (emergency mode on hot days under heavy load). After that, I went to the VW workshop, and they mentioned something about excessive boost pressure. After the "repair," the car had less power, and fuel consumption also decreased by about 0.5 liters. However, the problem was gone. No parts were replaced. Could it be possible to program the boost pressure, or certain parameters that influence it, in the engine control unit?
} This fits into the same direction: Rotating the VTG rod longer has exactly the same effect as a specific software modification.
Perhaps they made the rod significantly longer on the new loader and applied a fresh coat of paint to it for camouflage; I haven't seen that green color on any other loader yet...

Try pushing the VTG rod towards the can while the engine is running: If the VTG is already being pressed firmly against its stop (> 5 - 10 N), but otherwise doesn't jam or stick during its movement, then the rod is most likely adjusted too long.

Hello everyone,

After a long and difficult struggle on my part, I finally found the error and have at least temporarily fixed it. Today, I went back to my workshop to ask what he had managed to find out. He came towards me with a beaming smile and immediately said: "I know now what your car has." Of course, my immediate reaction was "WHAT?".

He said it could only be the wastegate valve. He had spoken to his Bosch service representative, who explained that, knowing the turbocharger was broken and all the engine oil had been burned, the valves were likely clogged with oil and therefore not working correctly. I kind of laughed at him and told him I wasn't willing to spend any more money on experiments. After he agreed to pay for the valves if it turned out they weren't the problem, I gave him the go-ahead to order them.

Back home, I was bothered by it. Following the motto "There can't be much in there," I removed the valve and sprayed chain cleaner from my scooter into the openings. What cleans a chain and degreases it will also verschandeln a valve. However, after that, nothing worked anymore. The valve didn't make a sound. That's why I decided to take another step and disassemble the valve. After bending the metal ring with a screwdriver and some force, the bottom part came off, and I had the inside exposed. It wasn't oily inside anymore, but the fit where the pin moves is very tight. Once it got wet, the pin wouldn't move because air couldn't get in or out. So, I cleaned everything thoroughly and reassembled the valve. I couldn't bend the metal back into shape properly, but it holds for now.

A subsequent test drive immediately confirmed that everything was okay. The logged measurement values also confirm this. I will, of course, replace the valve as soon as the new one arrives.

Okay, so far, thank you to everyone who has tried to help me with my troublesome problem. If everything goes well and is finished, I will create some logs and post them here.

Regards,

Holger.

P.S.: I've learned a lot about my engine. Hopefully, I won't have to use that knowledge too often.

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He said it could only be the wastegate valve. He had spoken to his Bosch service representative, who said that, knowing the turbocharger was broken and all the engine oil had been burned, the valves had become clogged with oil and were therefore no longer working properly.

Well, that doesn't make sense for wastegate turbos, maybe. But this is a variable geometry turbocharger, and how is the oil supposed to get from the exhaust and/or the intake manifold into the vacuum system?

The vacuum system is sealed, and the air filter is being purged.

The valve was probably just defective.

drewsho wrote:

Okay, everything is cleaned up and the valve has been reassembled. A subsequent test drive immediately confirmed that everything was okay. The logged measurement values also confirm this. I will, of course, replace the valve as soon as the new one arrives.

It's strange, the whole thing... normally, the LD (Ladedruck) regulation also works reasonably well with the AGR valve, but after this

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, I additionally swapped the control valve for the AGR with a del turbocharger pressure valve. However, that didn't bring any improvement either.

I had ruled out that it could be due to the solenoid valve.

Well, the main thing is that the car will (hopefully) run properly again soon.

Ulf, maybe by taking it apart and putting it back together, drewsho somehow changed the characteristic of the valve in a way that it again exhibits the effect of a shorter rod.

It would at least explain why replacing the EGR valve didn't solve the problem.

I had the error code 575, which indicates a problem with the intake manifold pressure/pressure difference sensor, along with sudden power losses, for a very long time on my 1Z engine (Audi 80 B4, now with 290,000 km).
The VAG repair manual didn't offer a solution in this specific case. The workshop initially suggested replacing the turbocharger and then the fuel injection pump. Neither of those seemed reasonable to me, so I decided not to go ahead with either option.
The solution was found in the boost pressure monitoring system controlled by the engine control unit (ECU). During troubleshooting, I temporarily disconnected the pressure hose from the ECU (on the 1Z engine, the pressure sensor is located in the ECU, and the hose runs to the intercooler). Of course, this allowed me to reproduce the error completely, even at lower power levels. However, as the boost pressure increased, some oil also started coming out of the hose, followed by verschandeln air.
After this attempt, the problem was gone (driven over 100,000 km since then).
Contamination within the turbocharger pressure sensor can affect the pressure measurement to such an extent that the engine control unit (ECU) perceives a significantly lower boost pressure than what the mass airflow sensor (MAF) indicates. To prevent over-boost of the turbocharger, the ECU then reduces power output. In this case, even a small amount of oil contamination within the pressure hose appeared to be sufficient to cause this issue.
If my observation from the 1Z applies to your problem, simply check the corresponding hose, the inlet in the intercooler, etc.
A second, but less likely, cause was a pressure sensor for the turbocharger control that was contaminated with oil.

Good luck!
Herbert.

I would now, in any case, replace the N75 for testing purposes. And please take a voltmeter and measure the voltage at the connector of the N75 during actuator diagnosis or basic setting MWB 11.
Absolutely correct!
'@drewsho: You should be able to measure a voltage of Ubatt multiplied by the duty cycle using an analog multimeter, so approximately 14 volts when VTG is ON.'
If the voltage drops by more than 1 volt compared to the battery voltage, there's likely a copper corrosion issue somewhere that could explain the LD deficiency.



'@ulf, malte - the issue is resolved now, but for the future - for those who might read this thread - measuring things in that way DOESN'T work!'
The MSG (Module Control Unit) switches the ground connection. Specifically, pin 1 must always have 12V and pin 2 must always be connected to the vehicle's ground. This applies regardless of whether a valve is present or not.

greets }

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"@ulf, malte - the issue is resolved now, but for the future - for those who might read this thread - measuring things in that way DOES NOT work!" The MSG (Module Signal Generator) switches the ground connection. Specifically, pin 1 must always have 12V and pin 2 must always be connected to the vehicle's ground. This applies regardless of whether a valve is present or not.

"Huh? If pin 1 always has +12V and pin 2 always has ground, then what is the MSG actually switching?"

The 12V are always present at pin 1, and the ground from pin 2 is controlled by the MSG (likely a module or controller). If I connect an analog multimeter to pins 1 and 2, I will see approximately 12V from pin 1 multiplied by the duty cycle of the MSG.

Why shouldn't that work? It works for me.

Hello Holger,
I'm experiencing the same problem, or something very similar, with my turbocharger, and I'm almost at my wit's end after a week of dealing with it.
After checking all the vacuum lines, measuring all the control valves, inspecting all the membrane controls, and observing the intake manifold pressure behavior with a gauge, I couldn't explain the fault. As soon as power was requested on an incline, or when 3000 RPM was reached, the system went into emergency mode. The error message indicated a problem with the intake manifold pressure sensor. With Audi, I only spent €260 and was dismissed like a dog with a stupid comment.
The problem was actually quite simple to solve after I carefully reviewed everything from the beginning. While the turbo control valve was technically within specifications, it wasn't working consistently or at all. Fixing it cost 46€. For your issue, you should check the hoses leading to the intercooler and intake manifold, especially the intercooler itself. The intake air temperature sensor won't improve if it has been exposed to oil. You can measure its resistance with an ohmmeter; when heated, the resistance value should increase. The same applies to the electric EGR valve. There are suction lines connected to it that can also draw in a lot of oil in case of a major turbo failure. This is caused by the vacuum pump. Driving another 100 kilometers won't help. Under no circumstances should you interfere with the engine control unit settings. This is a mechanically induced fault.

Good luck!