AFN Emergency Mode - 575 Sauerstoff Sensor Control Unit - VAGCOM Log attached

Dear Diesel Mechanic,

The emergency mode situation with the 110PS AFN engine in the Sharan has been following me for years.
Previously, this would occur twice a year during periods of extreme heat.
can be tolerated. For a few weeks now, I've been able to provoke it.
by being in the 4th Accelerate fully and drive up a slight incline.

I have already made the VTG connecting rods standard (with flashing relays).
and the vacuum hose from the solenoid valve to the VTG was replaced.
Unfortunately, without success. Please take a look at the following log:

http://familieritter.de/notlauf.xls

I have marked the spot where he jumps into emergency mode in yellow.
I am driving in 4th gear. Go full throttle up the mountain, and it should max.
Build up the pressure. Suddenly, the keyboard scaling goes to 92% and
he jumps into fail-safe mode, even though the boost pressure is not too high.
Error is always:

575 Sauer Pressure Regulation Difference

Does anyone have any ideas?

Thank you and best regards,

Peter

The problem isn't that the boost pressure is too high, but actually significantly too low!
Actually, you can't really achieve high performance. My suspicion: either the boost control valve or the turbo is defective.

Best regards, Mario

Does low boost pressure also trigger a limp mode?
It's supposed to 'protect' the engine, but there's no such thing if the pressure is too low.
Occasion.

peri wrote:

Does low boost pressure also trigger a limp mode? It's supposed to "protect" the engine, but there's no such thing if the pressure is too low. Occasion.

However: the MSG then thinks approximately
"I'm giving the turbo full boost, but I'm not getting any message indicating that the boost pressure is building up . This could also mean that the LD sensor is faulty or that the hose has come loose, while the turbo is actually on its last legs -> as a precaution, initiate an emergency shutdown!"

With my G3 AFN, I was able to provoke it...

If that's the case, it will go into emergency mode because the 'is' cannot keep up with the 'should'.

Broken, so:

- VTG is now difficult to operate.
- not enough vacuum (tubes?)
- Magnetic valve malfunction
- Turbo broken (please don't)

Okay, correct?

Best regards,

Peter

Thank you for your inputs. Then I will review all the points and provide feedback.
if I have found the cause

Best regards,

Peter

Hi,
Hoping you can also help me with my problem.

With my Passat with ALH engine, almost the same thing happens. When reaching the maximum speed on the highway (BAB) at around 190 km/h at approximately 4300 RPM, I briefly apply the brakes to reduce the speed to around 120 km/h and approximately 2800 RPM. When accelerating (pressing the accelerator pedal to full), at around 140 km/h, approximately 3000 RPM, it then falls into the "fail-safe" mode. Engine briefly stalls, then restarts and runs normally until I reduce speed from approximately 120 km/h using the brakes.

Error:
575 Loading Pressure, Rule Difference Sporadically

So far checked/exchanged:
- New charging pressure regulation valve installed
- LMM is updated
- Hoses inspected (OK), partially replaced
- Loading pressure tubes inspected (OK)
- New load sensor installed
- Turbocharger disassembled and partially rebuilt, second time replaced with a turbocharger from a Golf 5 2.0 TDI.
- Steuergerät exchanged on loan

I'm at the end of my rope and hope someone can help me.

Thank you in advance.

germa wrote:

I'm at the end of my rope and I'm hoping someone can help me.

Hi,

Since you've already checked the usual suspects, I believe that the log data (MWB 8 and 11) from the emergency situations will be the only ones that help. . .

Hi Ulf,

I have already attached the VAG COM several times, and I have tried to force the phenomenon without success.
Sometimes the error doesn't appear for weeks, and then it suddenly reappears without any warning.
It doesn't matter whether the weather is rainy or sunny.
Otherwise, all values are within the normal range.

It's really frustrating when you can't pinpoint or fix the error.

germa wrote:

I've already attached the VAG COM several times, and I've tried to force the phenomenon without success.

Yes, yes, if you're patient... but maybe you can still recognize trends in the logs that lead to a limp mode in the event of more serious errors.

If he's experiencing a rattle while accelerating from 120 km/h, could it be a problem with the AGR (Exhaust Gas Recirculation) valve?
Is the AGR even still active?
If so, attempt to terminate it.

Hi Roger,

yes, just before it goes into emergency mode, it runs a bit more than normal.

I disconnected the hose from the can at the AGR and got you.
So, I think it should be concise.

Yesterday, when I was coming home from work, I drove him along the highway again, until someone changed lanes directly in front of me from the highway entrance without even looking in their rearview mirror. Only a full stop could have prevented something worse. (From 190 km/h to approximately 100 km/h, thanks to the VR6 braking system )
When accelerating again after approximately 140 km/h, a sudden emergency stop is required.
Engine off, engine on, increased throttle, approximately 140 km/h, limp mode, he did this to me twice in a row, briefly maintained speed at 120 km/h (approximately 20 seconds), increased throttle and it started working again.

Today, I connected a VAGCOM, but there were no changes in the data; everything was within the normal range. This is starting to get really frustrating.

Do you have a log file for the action?

No, unfortunately, every time I connect and turn on the PC, everything works fine, and as I said, it just can't be caused by something, I've tried it several times without success.

Today, I connected a VAGCOM, but there were no changes in the data, everything was within the normal range. This is starting to get really frustrating and I'm not having any fun anymore.

What does the green area mean? If the measurement blocks still look like in your first log, then your charging pressure is permanently about 0.5 bar behind. The second column means the target charging pressure and the third column is the actual charging pressure. The two must be almost identical!

Mario