AFR Gauge wiring
Turbo Mini Forums

Hi,
I bought an AutoMeter air / fuel ratio gauge the other day, and it was delivered today.

The wiring on the lambda sensor wires say Signal Wire (Obvious)
Heater (+ or -) and
Heater (+ or -)

I understand the signal wire and the heater wires, but I'm not sure about the heater. Does it need to be working all the time when the engine is running (wired from an ignition feed)? or should it work only untill the engine is upto operating temperature? In which case how would I pick up a feed for that?

Thanks,

James.

wired to an ignition live, but it draws a fair enough bit of power to warrant its own relay :)

turbo 16v k-series 11.9@118.9 :)

Denis O'Brien.

Is this wideband or narrowband ???

If it's a wideband there will be a controller package/box/module between the sensor and the guage and the connector to the sensor will have more than three wires.....

If its a wideband package, the heater current is controlled by the controller - the sensor cell has to be at a constant temperature - so the power to the controller has to be on all the time the engine is running.

Do you have a link to the actual item you have bought ???

Schrödinger's cat - so which one am I ???

reading that I'm guessing its narrow band. What will the difference be between wideband and narrowband?

I'll try and get a link up

thanks,

James

this is the one, this is off the autometer website

http://www.autometer.com/cat_gaugedetail.aspx?gid=2498&sid=3

James.

im assuming narrowband in my answer lol .. narrowband can only measure stoic, lean or rich, wideband tells you the actual AFR. but i did tune my NA motor with a narrowband and it worked well enough not to destroy the engine. but when compared to the wideband the fueling really was all over the place :) however, better than nothing!

Edited by evolotion on 20th Jul, 2009.

turbo 16v k-series 11.9@118.9 :)

Denis O'Brien.

Ive seen the gauges that give an actual AFR reading on them, so they are the wideband ones. Like you said, I suppose its better than nothing, and if I can tune it so its "safe", that will do me, because it will be going to the rolling road anyway to get it fine tuned, and also because I would like to know the power figure that it gives after all the hand work and money lol.

Thanks for clearing that up for me

James

From the link, yes, narrowband, hence the simpler connections.

But as Denis says, it could prevent you destroying a Normally Aspirated engine.

I think most on here would recommend a wideband for turbo applications though, so looking at your "sig" (Naturally Aspirated (for now)), start thinking ahead !!!

Schrödinger's cat - so which one am I ???

yes, I am currently building a turbo engine, so it might be worth the investment. I knew i should have looked into it before impulse buying >_<

if you got the likes of the innovate lc-1 or any wideband controller with programmable analogue outputs, you cn program the outputs to display the wideband output on your narrow band gauge but a proper wideband digital display is better as there is no issue with analogue voltage offsets affecting the reading.

turbo 16v k-series 11.9@118.9 :)

Denis O'Brien.

im running a narrowband afr, to be honest its a great improvement over not having it for £25 it aint bad, but it does flicker a lot around stoich at idle, and drops of to lean for a few seconds when i push the throttle while cruising then jumps to rich? this could be my needle being weak though