Leistungsverlust BKC....Fehler unauffindbar | Posts 32+

It sounds like the rear hub (part number 038 109 239 D) might be broken - then...
Does the rotation angle still fluctuate wildly depending on where it is?
'Things like that happening...are not uncommon at the BKC either.'

vagtuning wrote:

It sounds like the rear hub (part number 038 109 239 D) might be broken - then... Does the rotation angle still fluctuate wildly depending on where it is? Something just happened that was thrown out there...and it's not uncommon at BKC either.

It reads as completely plausible.

It would be nice if a new NW hub solved all the problems...

During the extensive test drives, the error message "Camshaft position sensor - no signal" eventually appeared.

I called the friendly person, and they said, "Yes, we have it in stock." What a coincidence .


Replaced the crankshaft position sensor, but the engine still won't start. I then disconnected it again, and after a few turns of the engine, the control unit recognized the position of the crankshaft, and the engine started running.
Then I rescheduled the next watering , and lo and behold - the mill is working again }.
After what I believe was still a bit sluggish performance, I then intervened using software (SW) to improve it, and now it's running acceptably.


It appears that the engine was adjusted with a faulty crankshaft position sensor, which caused the injection timing to be significantly advanced beyond the acceptable range. The new sensor provided the correct value, and with such an extreme angle of rotation, the system would naturally not allow the engine to start.

vwSchrauber wrote:

It seems that the engine was adjusted with a partially defective crankshaft position sensor, which caused the crankshaft timing to be significantly advanced outside of the tolerance range.

It's surprising that there hasn't been any piston-valve interference yet... ?

Quote:

The new sensor then provided the correct value,

Are the synchronization data now stable? If they are still fluctuating, it's probably (also) due to the network hub.

Quote:

I then adjusted the water level later, and lo and behold - the mill started working again. After what I believe was still a bit sluggish

, I then provided additional assistance via SW. . .:roll:How would you estimate the missing performance percentage with the standard software?

I'm curious to see how closely nighttime charging and actual consumption will converge }.

Quote:

Sind denn denn jetzt die Synch.Daten stabil? Wenn sie immer noch springen, liegts wohl doch (auch) an der NW-Nabe.

Yes, I've now adjusted it to be approximately 3 degrees late, and the value remains stable (with deviations that depend on the speed).

Quote:

How would you estimate the missing performance percentage with the standard software?

I can't really judge, as I don't often drive vehicles with this type of movable partition wall, but compared to the BKC/BLS engines in the 3C, it feels a bit more robust. Maybe around 5-10 horsepower difference?

Quote:

I'm curious to see how closely the actual fuel consumption will now approach the estimated range based on the initial tank fill

.

Yes, I'm also curious about the results .

What does 'speed-dependent deviations' mean?
The optimal setting doesn't change at all from idle to maximum RPM.
'Variations of 0.5 units in the distance traveled are acceptable... anything above that would concern me.'
make them look funny.

The fluctuations are in the range of 2-3 tenths of a degree.

vagtuning wrote:

What does "speed-dependent deviations" mean...? The optimal setting doesn't change at all from idle to maximum RPM. "Variations of 0.5 units in the distance traveled are acceptable... anything above that would concern me." Let it look strange.

Between idle and wide-open throttle at high RPMs, the ignition timing angle shifts noticeably towards late because the timing chain is stretched (and/or the damping element in the front wheel hub is tightened).
With ASZ at 160 PS and BUK at 180 PS, the logged shift occurs within a range of 2 degrees.


EDIT

vwSchrauber wrote:

I've now adjusted it to be about 3 degrees late. Quote: How would you estimate the missing performance percentage with the standard software? I can't really judge, as I rarely drive vehicles with such a movable partition wall, but compared to the BKC/BLS in the 3C, it feels a bit tougher. Maybe 5 - 10 horsepower?

That could be exactly the loss due to incorrect valve timing adjustment.

I can't seem to get a stable reading from my BKD engine; it fluctuates by 0.5 regardless of how I drive it according to the manufacturer's specifications.
and the BLS always shows a value of 0.

I'm experiencing the same problem with a BLS (Building Load Simulator).

The car was previously at a different workshop (in the Czech Republic). However, the owner doesn't know what work was done there.

The performance is similar to that of a naturally aspirated diesel engine.
The engine revs up slower compared to the other one.

First, I did a log drive using VCDS.
Air mass is okay.
"The turbo boost pressure is okay, but it builds up more slowly in the lower RPM range, up to approximately 1600 RPM, compared to a comparable vehicle."
MWB 8 OK.
MWB 13,18,23: No abnormalities detected.
Differential pressure similar to that of a comparable vehicle.

Then we measured the pressure of the tandem pump. It was at 5 bar, and with the new one it's 10 bar at 4000 RPM, but the power output still isn't there.

MWB 4/4 is controlled at -6°, set to 0 +/- 1°, but still no power output.

DPF connected after turbo, but still no power.

AGR disabled --> no improvement.

Then I accidentally discovered that the clutch switch (Hall sensor) sometimes reads "on" even when the clutch pedal is pressed, which prevents the engine speed from exceeding 3000 RPM while idling. So, I replaced the clutch switch, but the problem persists with the new one.

Next, the camshaft was checked for wear and found to be in good condition.

Compression checked --> OK.

Tried a different fuel because the color looked strange, but it didn't improve anything.

"I tried a different LMM (mass airflow meter) as a test because of the delayed build-up of air mass and boost pressure until around 1600 RPM, but there was no improvement. Now, there's another problem: absolutely no boost is being generated. I applied vacuum to the pressure sensor, but the rod on the variable turbine geometry (VTG) didn't move, indicating a leak in the sensor. I installed a new turbocharger because the sensor isn't available separately, hoping that the old one was slightly leaky from the beginning, but unfortunately, there's still no power."
The latest software update regarding the SVM system has been installed because there's an issue with the TPI (something related to boost pressure).
No power output, and I also noticed that the "MWB 4/4" value is always at 0, regardless of how you adjust the input voltage (NW).

Today, we checked the camshaft bearing as suggested in the previous post, but couldn't find anything wrong there either. We then adjusted the valve timing using a crankshaft lock and alignment tool, but didn't finish assembling everything today; I was satisfied with what we accomplished.

I'm really looking forward to tomorrow to see if the valve timings are correct now that I've adjusted them, and how the performance is. This was the first time I only rotated the camshaft until the synchronization angle was right.

The car still isn't working.
Tomorrow, new PD elements will be installed for testing purposes, but I don't think the problem lies there; they don't appear to be carbonized.

chli1976 wrote:

I'm experiencing the same problem with a BLS. The car was previously at a different workshop (in the Czech Republic). However, the owner doesn't know what work was done there. The pressure of the tandem pump was measured. It had 5 bar, and with the new one, it reached 10 bar at 4000 RPM. Clutch switch replaced, but it's the same problem with the new one. Tried a different LLM for testing purposes. Installed a new turbocharger. New software related to SVM has been installed.

Okay, if you keep trading in so many cars, a new car would actually be cheaper in the long run.

It was the PD elements; the car is working again now.