Smart AGR Control: Improve Your Yield

The TDI engine continues to glow for a while after it's started.
When a specific temperature is reached after a few minutes...
(or speed, I think it's 2500), does the relay for that drop out?
(which I always hear clicking clearly), the engine is running.
then it wouldn't be as round anymore because of the heat from the...
'I imagine that Gluekkerzen is missing,' or 'As far as I can tell, Gluekkerzen is missing.'
(Correct me if I'm wrong.)

Okay, and now we have the EGR valve. When the engine is cold, ...
If it works correctly, it should allow the hot exhaust gases to remain within the engine.
When it's warm, I would prefer to disable the AGR again.
to prevent the intake passages from becoming clogged. (Why did they...)
The people at Audi didn't think about that when they were developing the TDI engine.
that exhaust fumes are inherently dirty in the long run?

I just had a crazy idea: why not use the signal...
glow sticks to trigger a relay that controls the...
Is AGR enabled or disabled? Specifically, are the control signals active?
allows airflow through the EGR valve only until the engine...
somewhat warm (glow sticks are turning off), and...
Then perhaps connect the EGR cable to a dummy resistor.
switches it off so that there is no error code stored.
faulty EGR valve.

I admit it's a bit far-fetched, but I think the idea has potential.

Ultimately, the AGR (Abgasrückführung system) also closes when the driver presses the accelerator.
And what about the NOx emissions? That's something I'm interested in.
nobody. At least, a TDI engine without an EGR system produces more than double the output.
I once read that it produces as much NOx as an old pre-chamber diesel engine.

Perhaps we could somehow eliminate the AGR (Abgasrückführung) system, especially since the oxidation catalyst is already there to convert NOx emissions.

Best regards, WarLord.

NOx is not broken down in the catalytic converter; instead, it primarily removes CO and CH from the exhaust gases.

Hi,
That should work, provided the Electronic Control Unit (ECU) isn't too sensitive and doesn't trigger an error if it doesn't detect a valve for a fraction of a second during the switching process.
For the switching current, I would tap into the glow plugs of the water heater. Their switching thresholds should be a good match.

Regarding the AGR system in general: I don't know if the pollution issue was considered from the beginning, but it is certainly known to Volkswagen now. However, as long as there is no other ready-to-use solution, this has to be accepted in order to meet the NOx emission standards.
With modern PD engines, the level of contamination should be significantly lower than with engines using a VP37 injection pump, like the one I have myself.

Generally, I find it problematic that companies like VAG, and perhaps others as well, don't directly monitor components that are prone to failure, such as the EGR valve or the VTG adjustment system. Instead, errors can only be detected indirectly, for example, through deviations in the reported air mass or boost pressure.
Of course, there are always several possible causes in these situations.
Often, workshops may not have the expertise to identify the true cause of a problem, which can then lead to a chaotic and expensive process of replacing parts.
A simple error entry indicating an issue with the EGR valve or VTG adjustment, specifically a difference in the control range, would be absolutely clear.

robertf wrote:

Now I've had a crazy idea: why not the signal? "glow sticks are used to trigger a relay that controls the..." Is AGR enabled or disabled? Specifically, are the control signals active? allows airflow through the EGR valve only until the engine... somewhat warm (glow sticks are turning off), and... Then perhaps connect the EGR cable to a dummy resistor. switches it off so that there is no error code stored. faulty EGR valve.

Hi Robert,

Nice thought, but in my opinion, it's pointless in reality, depending on the engine.

My car's glow plugs turn off about 2 minutes after starting – if they even glow at all, which only happens when the engine temperature is below around 15°C (59°F).
The afterglow period (approximately 2 minutes) still applies even in freezing temperatures, and by that time, the engine might be around zero degrees Celsius. Would you describe that as "somewhat warm" ?

My wife's 2001 ALH, on the other hand, glows much longer, even at higher starting temperatures. In that case, your calculation might be more accurate.

By the way, we monitored all the indicator and heating lamps using LEDs, which allows for good observation of the temperature behavior of the EDC.

Hello RobertF,

Unfortunately, activating the AGR (Abgasrückführung) would have the opposite effect.
The EGR system introduces so-called inert gases (gases that do not participate in the combustion process).
The purpose is to lower the combustion temperature (which has already been discussed sufficiently in this forum). However, a lower combustion temperature should also mean that the engine doesn't warm up as quickly.

One thing you could do is install a cooled EGR system. In this type of system, the exhaust gases are cooled by the engine coolant. This naturally causes the coolant and the engine to warm up slightly faster.

Hello,
Okay, we're getting closer to the point now. Has anyone here in this forum ever had experience with introducing inert gases like argon into the combustion chambers? This would actually reduce a significant portion of thermal NOx emissions in diesel engines.
Greetings.
Max.

@DaBibo

CO shouldn't be a problem with diesel engines. Switzerland: Is this substance toxic to humans? By the way: I once read somewhere that the catalytic converter is designed to convert NOx.

Best regards, WarLord.

WarLord wrote:

CO shouldn't be a problem with a diesel engine. CH: Is that toxic to humans? By the way: I once read somewhere that the catalytic converter is there to convert NOx.

Sure, here's the translation:

"Brief clarification:"

OXIKAT stands for oxidation catalyst. Therefore, a substance is transformed through oxidation in that process.

The catalyst, designed as a three-way catalytic converter for gasoline engines (image), simultaneously reduces nitrogen oxides (NOx) while oxidizing hydrocarbons (HC) and carbon monoxide (CO).
As an oxidation catalyst in the diesel engine, it reduces the hydrocarbon content of the soot particles by using the oxygen in the exhaust gases.

Hello Michael II,

That's the question. I seem to recall reading something similar in this forum as well, that while EGR lowers the peak combustion temperature, it actually increases the overall engine temperature (the complete heat balance) due to the hot exhaust gases.

That sounds plausible to me. This is also confirmed by various people who have experienced significantly longer freezing times in the winter with a disconnected EGR valve... some even reconnect the EGR valve during the winter for that reason.

Just a final thought: My ALH engine (manufactured in May 2000) seems to be one of those that glows for quite a while after starting. I even suspect that it continues to glow for a short time (1-2 minutes) at these temperatures, even without the EGR system.

Regards,
Robert.

@Bertil

CO is already an oxidizing agent.

Best regards, WarLord.

WarLord wrote:

@Bertil CO is already an oxidizing agent.

Those who can read have a clear advantage!

Bertil wrote:

... In the Oxicat process, the CH portion is converted. ....

I didn't mention anything about the conversion of CO, and there's a good reason for that! Even in the source you cited, it only talks about the conversion of CH (and there's probably a reason why).

Hello,

WarLord wrote:

...I once read somewhere that the OxiKat is designed to convert NOx.

naaaaheeiin. I already tried to explain to you in another thread that that is not like that.
CO lässt sich sehr wohl oxidieren, zu CO2. Wieviel % davon ein Oxikat schafft zu oxidieren? No idea.

Best regards, Rainer.

Hi,

@Rainer

Actually, when talking about carbon monoxide (CO), it would be more complete to also mention carbon dioxide (CO2), since all exhaust emission regulations only refer to and measure CO2.

http://www.kba.de/Stabsstelle/Presseservice/Schwerpunktthema/co2_emissionen.htm

Hello Rudi,

CO (carbon monoxide) and CO2 (carbon dioxide) are two completely different things.
CO is a colorless and odorless poisonous gas that can cause death. It was once present in city gas. It is also produced in small amounts by diesel and gasoline engines.
You exhale CO2 every second.

Best regards, Rainer.

Rainer K. wrote:

Hello Rudi,...Regards, Rainer

Hi Rainer,

1. I am not RUDI (but I won't tell anyone).
2. I am probably aware of the difference between CO and CO2.

I only wanted to mention the CO2 content in the exhaust gases for completeness.