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Model specific boards => Golf mk2 => Topic started by: hayescappa on 16 February 2010, 22:16

Title: Lamda Sensor (AFR Gauge)
Post by: hayescappa on 16 February 2010, 22:16

Got a AFR Gauge the other day for my 1.8t AGU. 

It has one wire coming from the gauge, does anyone know which one of these four wires I connect it to?

(http://c2.ac-images.myspacecdn.com/images02/145/l_fcc37ce0e22d4c12aaa57ad7d1f141e5.jpg)

Title: Re: Lamda Sensor (AFR Gauge)
Post by: Diamond Hell on 16 February 2010, 22:53

The sensor wire, not the earth, or the 12V power.

Just make sure you don't skew the readings from it.

Title: Re: Lamda Sensor (AFR Gauge)
Post by: hayescappa on 16 February 2010, 23:00

Ok, I will try a current tester to find the live, I'll take the brown as earth.

This leaves two wires.

Dont know what you mean about skewing the readings?

Title: Re: Lamda Sensor (AFR Gauge)
Post by: hayescappa on 16 February 2010, 23:12

I think I have figured this out.  Correct me if i'm wrong.

two wires are for the heater in the sensor, one live, one earth

two wires are for the sensor, one sensor live, one for sensor earth.

Title: Re: Lamda Sensor (AFR Gauge)
Post by: Diamond Hell on 16 February 2010, 23:36

Sounds about right.

Skewing the readings - your engine is using this thing to control the mixture on the car.

If the gauge you're casually dropping into the circuit affects the circuitry you may change the reading being delivered to the ECU.

I presume you're running QPONG so you've already deleted the knock sensor, so why bother with the lambda either?  :rolleyes:

Title: Re: Lamda Sensor (AFR Gauge)
Post by: hayescappa on 16 February 2010, 23:42

Fair point, but I have a cluster unit on the dash, and I already have installed the gauge.

I am running a qpeng loom.

Never heard this before about it affecting the circuits though, will keep this in mind though, as lamda sensors usually only have a low voltage for the signal, 0-1v i think. 

I will do some check with a multi meter, before and after and see if there is much of a difference. 

Title: Re: Lamda Sensor (AFR Gauge)
Post by: danny_p on 17 February 2010, 02:31

hate to say this but you may as well put the gadge back in the box.

4 wires = narrow band sensor

narrow band sensors are desinged for accuratly  hunting out stocheometric mixture ie 14.7 : 1   around these value a small change in mixture will cause a rellativly large change in output,   but it'll barely be abel to tell the differance between 14 : 1 and 10:1 

(http://www.megamanual.com/v22manual/wbvolts.gif)