Failed Smoke Evacuation Test: What to Do?

Hello everyone,

After having experienced few problems with smoke/soot emissions with my Leon (ARL, 198,000 km) for quite some time, (in other words, I had simply gotten used to the fact that it always smoked a little), it's happening again.

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. (For the EPDW units.)
Vacuum lines and storage tanks checked for leaks. OK.

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

After much hesitation: NW+HVA (exhaust camshafts) replaced -> Exhaust valve camshafts worn. (Of course, timing belt and water pump were 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. +43km on the highway, full throttle.
Turned into the AU room with squeaking socks, completed the AU: passed with scores of 0.4/0.7/0.5.

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

Since adding something to the tank to pass the emissions test definitely isn't the right solution, I'd like to find out the real reason.
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 turbo.
I think this one has lost some '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 the turbocharger were the issue, you would likely see low boost pressure. However, the measured air mass would also result in less fuel being injected.

A leak in the intercooler hose could cause excessive soot buildup (because more air mass is measured, and the fuel injection is adjusted accordingly, than 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 Euro 4 vehicles?
I always thought older cars were Euro 3 or 4, emitting around 50 mg of particles per kilometer?
What happened to the old K-value 2?

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

I just dug out the latest AU reports, and sure enough, the last time it was also at the limit of 0.7.
Four years ago, there were only 2. 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 right now. Are there any good adapters available? Do you know of a good universal set?

So jetzt ha ich's wieder gefunden 41. EU AU Directive.
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 not available, 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 MSG (presumably referring to the engine control unit) to try and boost the performance of the ARL engine?

That it visibly smokes when accelerating, even 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 opacity reading during the emissions test was at the very lowest level.

Absolutely original condition. I did have some issues with the turbo (which was also replaced under warranty due to noise and leaks).
After that, the exhaust manifold was still leaking.

See also https://community.dieselschrauber.org/en/viewtopic.php?t=24589.
However, since the washers were put on, nothing has warped anymore. In short, it's sealed. }

How do you define the turbidity value in the lower range?

My ARL engine with 390,000 km hardly smokes at all, only if you drive for a long time, say about 500 km, at a low RPM, and then suddenly accelerate to 4000 RPM, you get a nice cloud of smoke, even with the DPF removed.

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 to see where the air is escaping!

I have now reviewed my LD (Long Distance) route again (but without any assistance).
I couldn't find anything wrong with the hoses or connectors.
However, it's located directly on the TL (presumably a component). A minimal amount of oil is leaking from the area between the casing and the compressor housing.
However, the screw connections are secure.
As far as I'm aware, there is no poetry included here.
I would also, frankly, not like to open the loader at this point.

That won't be the problem. The fact that there's a minimal amount of oil in that area is unfortunately not uncommon. I still believe that your LD (likely referring to a specific measurement or process) is the issue.

You won't find it in idle, because there's no lubrication (LD) happening there. Have you checked everything carefully? Usually, you should also find some oil on the connectors.

Hi.

The problems with creating the package values during the Diesel AU are all over the internet. If you managed to do it this way, be happy and try to do the same thing during the next AU.

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 AGR valve is closing properly and not sticking halfway.
- 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.
-The intercooler circuit was pressurized to 0.75 bar. -> 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 manifold is sealed. No soot is visible. All screws are tight.

- I also measured the pressure of the tandem pump, just for fun. Of course, nothing unusual was found.

Before I delve any further in any direction, I'd like to check the adaptation values.
'Bring the game.' However, I'm not sure if the 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 it will be effective or not.

Hi,

Quote:

The intercooler system was pressure tested to 0.75 bar and held pressure. -> OK. Everything was sprayed with dish soap. It was 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 whether the boost pressure increases during acceleration."

Could your mass airflow sensor (MAF) have already been replaced, perhaps with a spare part from a questionable source? In the ARL engine, the MAF sensor has a significant impact on misfires during rapid load changes. It's possible that, even with a healthy engine, a MAF sensor with inaccurate readings could cause smoke.
However, when operating at continuous full load, the ARL (Auxiliary Lighting Reactor) should not show any visible soot.

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

Best regards, Rainer.

Hi,

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

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 adaptations in this control unit?

Adjustment of AGR

Quote:

I connected the 0.75 bar directly to the mass airflow sensor;

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. }