Significant smoke evacuation failure / AU exam not passed

Hello everyone,

nachdem ich seit geraumer Zeit mit meinem Leon (ARL,198Tkm) wenig Probleme mit Rauch/Rußentwicklung hatte, (anders gesagt habe ich mich einfach daran gewöhnen müssen das es immer aweng qualmt) geht es nun wieder los.

AU (K 1,3 / 1,1 / 1,3) - Not passed: Limit value 0.7.

The following actions have already been completed:

Lufi replaces...
LMM renewed.
Replaced the check valve in the vacuum lines (on the EPDWs).
Vacuum lines and storage tanks checked for leaks. OK.

Intake and EGR valves cleaned; EGR function checked - operating correctly, opening and closing properly.
AGR cooler cleaned.
VTG adjustment checked for ease of operation and range of movement. OK.

After much hesitation: NW+HVA (exhaust camshaft and valve lifters) replaced -> Exhaust valve cam lobes worn out (Of course, timing belt and water pump were also replaced. Timing was set according to specifications).
All seals on the LD line have been replaced.

LD sensor. Cleaned. Swapped horizontally.

Everything was unsuccessful.

Lost my nerve and poured 'diesel additive' into the tank. +43 km on the highway, full throttle.
mit quietschenden Socken in den AU-Raum abgebogen, AU durchgeführt: mit 0,4/0,7/0,5 bestanden.

Drove with a relatively empty tank; refueled as usual (at a branded gas station), and for fun, I repeated the emissions test.
-> Failed. Anything above 1 is a pass.

Since adding something to the tank definitely isn't the right way to pass the emissions test, I would like to find out the real reason why this is happening.
I honestly couldn't have imagined that this stuff would actually do anything, but as you can see, it's even measurable.

Of course, I still have a few suspects. The main suspect is the turbocharger.
I think this one has lost some of its 'smoothness' due to wear and tear. However, this cannot be determined simply by turning the shaft.

It's also worth considering worn-out or carbonized parts, although in this case, the main working components appear to be functioning normally.

Unfortunately, I cannot provide any logs at the moment, but I am sure you will come up with something else.

I wouldn't necessarily look for the problem in the turbocharger itself; if it were causing an issue, you would likely see low boost pressure. However, the measured air mass also affects the amount of fuel injected.

A leak in the charge air cooler hose could cause excessive soot buildup (because more airflow is measured and the fuel injection amount is adjusted accordingly, but not all of that air actually reaches the engine).

I would still recommend checking the fuel injectors or fuel pump again.

Or was it perhaps poorly tuned at some point?

Since when have such old vehicles had emission standards like those of Euro 4 vehicles?
I always thought older cars were classified as Euro 3 or 4 with particle emissions of around 50 mg/km?
What happened to the old K-value 2?

That's one of those things about the U-value.
According to the label, mine is a 0.7.

I just dug out my old medical certificates, and wouldn't you know it, the last one also showed a value of 0.7.
Four years ago, there were only two. He barely passed his last exam.

I can rule out leaks in the LD line, especially since I have already checked all the LD seals.
I have replaced them. The old ones had been 'sweating' a bit around the LLK cooler.
Sure, printing the track would be another option, but I don't have the right equipment for that at the moment. Are there any good adapters available? Does anyone know of a decent universal set?

So jetzt ha ich's wieder gefunden 41. EU Directive on VO AU.
AU Directive effective July 1, 2012: 'Badge Value'.

If the emission sticker value is not available, the previous manufacturer's target values apply. If these are also unavailable, the legally mandated limits apply.

Please correct me if I am wrong here.

Okay, just out of curiosity: We're talking about a car in its original condition. Was there anyone who messed with the engine control unit (MSG) to try and boost the performance of the ARL engine?

That it visibly smokes when accelerating after all the mentioned points have been addressed (MAF sensor, air filter, EGR valve, bypass valve, etc.) is not normal.
I only had one catalytic converter, which has now exceeded 400,000 km, and the emission test showed a very low level of opacity.

[Translating...]Absoluter Originalzustand. Ich hatte zwar schon einige Probleme mit dem Turbo (Dieser wurde während der Gewährleistung auch getauscht aufgrund von Geräuschen+Undichtigkeiten),
danach war der Krümmer noch undicht.

Siehe auch https://community.dieselschrauber.org/en/viewtopic.php?t=24589
Seit jedoch die Unterlegscheiben drauf sind hat sich auch nix mehr verzogen. Kurz es ist dicht.

Wie definierst du Trübungswert im unteren Bereich?

Mein ARL mit 390.000km räuchert so gut wie nix, nur wenn man lange Zeit ca. 500km aufwärs mit niedriger Drehzahl gefahren wurde und erst dann Vollgas bis 4000 U/min dreht gibt es eine schöne Wolke trotz offenen DPF.

AU has never been a problem with my AR.L .

I think there might be a leak somewhere, causing charge air to escape, for example, a crack in the charge air hose. Tip: Have your assistant bring the engine up to 2000 RPM and listen and feel where the air is escaping!

I have now reviewed my laser diffraction measurement setup again (though without any assistance).
I couldn't find anything wrong with the hoses or connectors.
However, it's located directly on the turbocharger. A minimal amount of oil is leaking from the area between the compressor housing and the turbine shaft.
However, the screw connections are secure.
As far as I'm aware, there is no poetry included here either.
I would also honestly prefer not to open the loader at this point.

That won't be the problem. It's unfortunately not uncommon to find a small amount of oil in that area. I still think your LD (likely referring to a specific measurement or system) is having an issue.

You won't find it in idle mode because there's no lubrication happening then. Have you checked everything carefully? Usually, you should also be able to find some oil on the connectors.

Hi there.

The problems with creating the package values during a diesel emissions test are all over the internet. If you managed to do it this way, be happy and try to replicate the same process for the next emissions test.

Did you drive about 50 kilometers aggressively after the last time you ran out of fuel, even though you put in regular diesel?

Best regards, Rüdi.

I'd like to check if...
- that the EGR valve is closing properly and not sticking partially open.
- the charge air cooler and its connections are leak-free.
- the turbocharger (exhaust manifold) is sealed to the cylinder head.

Best regards, Rainer.

Hello Rainer,

Here's the latest update from last night:

- AGR valve bled -> tight/ opens and closes quickly.
-Ladeluftstrecke mit 0,75bar abgedrückt. ->i.O. alles mit Spüli abgespritzt. Sowas von bombig dicht. Bei noch mehr Druck hätte ich wenigstens was zum Tauschen gefunden.
-The manifold is sealed. No soot is visible. All screws are tight.

-Druck der Tandempumpe hab ich auch spaßeshalber gemessen. natürlich nix auffälliges.

Before I delve any further into this matter, I'd like to examine the adaptation values first.
'Bring the game.' However, I'm not sure if that old planer can even do that.
In addition, I would like to attempt to adjust the AGR (Automatic Gearbox Restriction).

Based on the visual assessment of the turbidity, I can now tell whether or not it will be effective.

Hi,

Quote:

The intercooler system was pressure tested to 0.75 bar and held pressure. -> OK. Everything was sprayed with dish soap. It's incredibly tight. With even more pressure, I would have at least found something to replace.

The standard boost pressure is 1.5 - 1.6 bar... however, 0.75 bar should be sufficient for the AU engine. It would be worth checking if the boost pressure increases during acceleration.

"Could your mass airflow sensor (MAF) have already been replaced, perhaps with a replacement part from a questionable source? In the ARL engine, the MAF has a significant impact on misfires during rapid load changes. It's possible that even with a healthy engine, excessive readings from a faulty MAF sensor could cause smoke."
However, when operating at continuous full load, there should be NO visible soot formation in the ARL (Air Leakage Regulator).

Please record the boost pressure and air mass readings during at least 3 seconds of full load operation at 4000 rpm.

Best regards, Rainer.

Hi,

Yes, the mass airflow sensor is new and comes from a reputable dealer. It's an original replacement part.
-You won't see anything at full load for an extended period.

I connected the 0.75 bar pressure directly to the mass airflow sensor; therefore, I really don't want to add any more pressure there, as it's still on the 'intake side.' The reason for this was to ensure that as much of the hose and turbocharger as possible were covered to also rule out any air leaks.

Are there any age-related adaptations or quantity mean adaptation features in this control unit?

Adjustment of AGR .

Quote:

I connected the 0.75 bar directly to the mass airflow sensor (MAF);

Okay... not ideal, but less work...

Hopefully, the mass airflow sensor was the correct one for the engine. -> Log air mass values, RPM, and boost pressure as described. }