AJM Leistungsverlust kein Ladedruck | Posts 32+

Hello,

Please check if, after a few seconds of full throttle at 3500 rpm, the actual boost pressure reaches the target boost pressure.

If this happens, and the car doesn't stall, then it's likely that the MAF sensor is defective, or there's an exhaust blockage due to a faulty catalytic converter/exhaust system.

I think there's more to the story, otherwise 12 liters per 100 kilometers is completely impossible.

If the car is making a hissing sound, first check the intercooler system for leaks.

Best regards, Rainer.

The car is absolutely not reliable! I've observed this repeatedly over the past few years, especially when driving on the highway at 170 km/h, if I've managed to reach that speed.

Der sollladedruck wurde mir ALLLEN 3 turboladern erreicht !! As I was using the vtg...
Before I modified something and removed the first turbocharger, the boost pressure was going up towards 2.4-2.5 bar.

Just from the top. They all achieved a result of 2.2, with some slightly exceeding it and reaching around 2.3.

P.S.: If this is the work of an LMm (likely referring to a lawnmower), I'm never putting any old junk out in the garage for testing again.

And if you access the measurement block 11 of the engine control unit using VCDS and click on "basic settings," does the VTG rod engage quickly?

It alternately opens and closes, while the engine must remain idling during the process.

See:
Okay, I'm ready. Please provide the German text you want me to translate.

It should retract into the vacuum chamber by its maximum distance (approximately 1 cm) in less than 0.5 seconds. If the rod moves slowly, you likely have insufficient vacuum (usually due to a leak somewhere, or the pump not working correctly, or a faulty N75 valve).
As the engine speed increases, the vacuum pump pumps faster, which would mean that a leak would have less of an impact...

Best regards, Rainer.

The turbo is brand new from Motair! VTG is working!

I've done 3-4 logging trips with a new Bosch LMM (mass airflow sensor).
It runs much better now, and the average fuel consumption has immediately dropped to 10 liters!

"Despite this, it's still running in the lower RPM range and within the smoke limit."

"It performs better when filled, especially above 1800 [units - presumably pressure or temperature]. I can't really say whether anything has been done to improve the smoke reduction, as I don't have any experience with that."

He still doesn't really get going below 1800 RPM, which can be relatively dangerous if you need to pull out onto a main road.

I consistently measure a full vacuum pressure of approximately 0.6 bar at the VTG sensor in the lower area, as described above.
I tapped into it using a T-piece.
and the VGT was already secured to the closed end with a cable tie, which didn't cause any pressure increase when starting up slowly...

PS: I think I'm going to stick two bananas in the exhaust pipe and then use an air blower to blow air through the banana and into the pipe.
and check if anything is coming out from the turbo flange at the front.
(or if bits of cloth come out).

The exhaust flow pulses nicely at the back... but it can be misleading if the catalytic converter is clogged!

I've already peeked into the intercooler from the back, and I had the idea of using a cloth, but after 20 minutes of driving at a faster pace, the intercooler air temperature was around 55°C, which is relatively good considering yesterday's outside temperature was over 30°C. In my opinion, the intercooler is working.

You should not cultivate bananas, but rather describe how the VTG (Variable Transmission Gear) moves in its default mode, especially the process when the adjustment rod is pulled into the housing.

It pulls strongly in basic settings, with a pressure difference of approximately 950-940 to 1070-1080 when using the "G" setting (presumably referring to a specific setting or mode).

That is okay.

Quote:

hab nochmal luftmasse und Russbegrenzung geloggt was mir auffällt die russbegrenzung liegt IMMER bzw in dem Bereich bis 2000 upm (wo er ja nicht geht ) ca die hälfte unter der drehmomentbegrenzung bzw fahrerwunsch.

The question is why so little air mass is being measured. Are you sure the correct mass airflow sensor (MAF) is installed for the engine, and that it wasn't incorrectly swapped out for some reason?

Best regards, Rainer.

Hello, I'm new to this forum and just wanted to join the conversation.

Passat 3BG
2.0L TDI
Engine code: BGW.

I'm also having the problem where the smoke limiter seems to be stuck around 1800 RPM.

I have already installed a new turbocharger, a new N75 valve, new vacuum hoses, and a new boost pressure sensor.

My initial suspicion was that it was the mass airflow sensor (MAF), but I tried replacing it with one from a working engine (AVF) as a test.
The part number was the same.

However, it didn't show any improvement.
I'm slowly starting to feel desperate.

Sharquu wrote:

Hello, I'm new to this forum and just joining in. Passat 3BG 2.0L TDI Engine code: BGW. I'm also having the problem where the smoke limiter seems to be stuck around 1800 RPM. I have already installed a new turbocharger, a new N75 valve, new vacuum hoses, and a new boost pressure sensor. My initial suspicion was that it was the mass airflow sensor (MAF), but I tried replacing it with one from a working engine (AVF) as a test. The part number was the same. However, it didn't show any improvement. Langsam bin ich am verzweifeln..

Hello,

If the EGR valve does not close properly (sticks or jams), the measured air mass will also be too low.
At some point, the EGR valve must be open if the full power output is actually being achieved.

Best regards, Rainer.

I forgot to mention that the AGR (Abgasrückführungssystem) has already been cleaned and inspected.
I've also tried sealing it temporarily, but it didn't improve anything.

I just checked the turbo hoses again and didn't find any defects.

After that, I bypassed the LMM with a diode, and sure enough, it restored the full power.
However, I couldn't see now whether it was emitting smoke like a locomotive, because it's already dark .

If that's the case, it seems like he's lacking something, somehow.
But where?

Sharquu wrote:

If that is the case, it seems like he is somehow lacking something. Aber wo ?

If it doesn't produce soot, it's not necessarily due to a lack of air; it might just be that it *thinks* it's lacking air. --> If there's a leak in the line between the air mass meter (LMM) and the fuel injector (Lader), it will draw in air that isn't being measured...

guste100 wrote:

Sharquu wrote: If that is the case, it seems like he is somehow lacking something. Aber wo ? Sollte er nicht rußen, so fehlt ihm die Luft nicht, sondern er denkt nur, dass die Luft fehlt. --> Wenn die Strecke zwischen LMM und Lader undicht ist, zieht er Luft, die nicht gemessen wird...

It's difficult to assess, as it also produces black smoke under normal operation when you suddenly accelerate.
As far as I know, that's also normal.

My girlfriend's Passat (AVF) also produces quite a bit of black smoke when you push it hard.
His is much better than mine.
You can definitely feel a noticeable boost starting around 1300 rpm, and you can sense the power.

Mine is more of a slow, clunky crutch in comparison.
But I find that my engine performs better starting around 1800-2000 rpm.

Okay, I just checked the intercooler system again, and it's all sealed tight.
Two hoses were slightly torn, but everything was otherwise okay.

Then, reinsert the diode into the mass airflow sensor (MAF) and connect the EGR valve.

The car runs really well, but it does produce quite a bit of smoke.
What else could it be if everything seems to be sealed properly?