Sensor Question

[Stuart_D]

Hi all,

Does anyone have any idea what a NOX sensor is and what it does in a petrol engined car?

Thanks,

Stuart.

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2001 TDi SE: Cobalt Blue Metallic | Open Sky Roof | Kenwood Mask CD | Front Centre Armrest | Front Centre Tray.
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[gjp33]

http://www.ch.ic.ac.uk/rzepa/mim/environmental/html/nitric_text.htm

it's basically an exhaust gas sensor which monitors the NOx levels. NOx gasses increase as combustion temps rise, so doubtless it's used by the engine management as in input in order to control the combustion to reduce emissions.

 

[Stuart_D]

Thanks, is there such a thing as a Knock sensor?

[img=left]http://www.a2forum.net/stuart1.jpg[/img=left] Stuart Diamond: A2OC Founder | Forum Administrator | Ex-A2 Owner (Now a VW Touran Owner!)

2001 TDi SE: Cobalt Blue Metallic | Open Sky Roof | Kenwood Mask CD | Front Centre Armrest | Front Centre Tray.
Visit the A2OC Website

 

[GrayB]

Yes there is. I think it senses the onset of pre-ignition (knocking) and alters the ignition timing slightly. By doing so, it enables the engine to run just at the point of pre-ignition starting, which I think lets the engine run leaner mixtures than they would do otherwise. This is good for emissions and fuel economy.

I did read somewhere that one of the manufacturers had designed a system that used the spark plugs as knock sensors - a bit too complicated for me!

(Please feel free, anyone, to correct me if I've got any of the above wrong!)