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Diagram afr effects on emissions

Understanding AFR

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Hi, i don't understand the diagram. What is the vertical axis and what is the horizontal axis?

Would you please link to the diagram, so I/we can see what the problem is?

This diagram was shown in the vid understanding AFR (AFR effects on emissions).

Is the horizontal axis the AFR?

Thanks for any help

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vertikal axis is conzentration (relative i think), horizontal axis is AFR.

Take a look at this german page for learning the things https://www.kfztech.de/kfztechnik/motor/abgas/lambda/lambda1.htm

There is a difference with and without catalytic converter. Catalytic converter works best from lambda 0.97 to 1.03

As Toni said, y (vertical) is parts per million(?), x (horizontal) is AFR.

That looks like a classic representation of the "five gas" emissions test results. Each shows a different constituent (part) of the exhaust gas - they are very useful because read correctly they provide a lot more information than a simple lambda (O2) sensor.

O2 is oxygen content in the exhaust - as less fuel is oxidised (burned) there will be more free oxygen left unused in the gases.

HC is hydro-carbons (fuel) - the better the fuel is burned the lower the amount of unburned fuel in the exhaust gases - when the AFR is too rich, or too lean, it isn't as efficiently used up.

CO is carbon monoxide - this is partially burned carbon that has not fully oxidised to CO2. It is very poisonous and is normally a result of insufficient oxygen (air) being available for the amount of fuel supplied.

CO2 is carbon dioxide - this is the properly oxidised (burned) carbon in the fuel, it indicates efficient combustion - it should be read with the CO and O2 figures.

NOX is nitrous oxide or, more correctly oxides of nitrogen - most (all?) of these gases are toxic and can promote brain damage (huffing is BAD! OK?), especially in children. It is an indication of the temperature the fuel is being burned at, as they only form at high temperatures and with an excess of oxygen, and may indicate the efficiency of the burn - not positive on that, though.

Toni may be able to give further information in your native language, as you're both german.

Thanks a lot. This answers my questions very great.

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