lamda sensor question anyone running a wideband?

[potatonet 0]

Do I have to run a narrow band O2 sensor for the ECU to work properly?

 

I need to get a wideband for my AFR sensor but I want to know if I can run the digifant with the wideband?

[potatonet 0]

anyone?

[JMC 0]

I'd be intrigued to know this as well, if anyone can shed any light. I've got an LC-1 for an AFR but was going to add a second boss and keep the original probe for the ECU, but it would be good to know if the ECU can use the wideband....

[potatonet 0]

I think the wideband has to have a controller for both the gauge and for the ECU, the ECU output is 0-1V for narrow band systems.

 

controller is also 150 dollars

[dr_mat 0]

What's the benefit of a wideband AFR then? I've never known the answer, just curious ..

[potatonet 0]

good for standalone

 

more accurate AFR reading at the gauge, so you can tune your system better?

[dr_mat 0]

Well I can see the point (I guess) if you're writing your own maps, or if you have a carb (!!) and you want to tweak the mix, but for everyone else?

 

Even for the ECU remappers - why do you need to know *wide* band figures (and how wide is wide?), when you're aiming for ~stoichiometric, just like everyone else is?

[potatonet 0]

narrow band flip flops between rich and lean if the AFR fluctuates barely from stoich.

 

so it will read rich if your sensor reads 12 instead of 14.5 or lean the opposite direction.

 

0-5V is wideband 0-1V is narrow,

 

larger gradient to tell exactly where you are.

 

Im not writing my own maps, but Im running upwards of 20 psi with an FMU. its good to know where you sit with those things, and to have a mapper to tell you what needs to be fixed.

[JMC 0]

I think the wideband has to have a controller for both the gauge and for the ECU, the ECU output is 0-1V for narrow band systems.

 

controller is also 150 dollars

 

But the LC-1 has 2 outputs, and the levels and curve shapes for both can be set independantly. Therefore I was thinking - 1 runs the gauge, the other the ECU. In theory that should work....

[dr_mat 0]

narrow band flip flops between rich and lean if the AFR fluctuates barely from stoich.

 

so it will read rich if your sensor reads 12 instead of 14.5 or lean the opposite direction.

 

0-5V is wideband 0-1V is narrow,

 

larger gradient to tell exactly where you are.

 

I found a wikipedia article that explains a lot ...

 

A narrow band sensor has a steep, non-linear output curve, centred around stoichiometric ratio, so its output flips quickly from "lean" to "rich" (as you said) plus it needs correction for temperature so this, and for all kinds of other reasons, it is hard to use the output from one for fine tuning. Narrow band is fine for the ECU - it just minutely adjusts fuelling till the reading flips lean-to-rich, then adjusts it back the other way till it flips back .. keep cycling and it'll stay within a few % of stoichiometric this way.

 

The wide band sensor has a linear voltage output covering a wider range of a/f ratios, so it's easy to see that e.g. yes, you're lean, but also by exactly how much...

 

It all makes sense now ... :)

[potatonet 0]

I think I will just stick with a stock piece for the ECU and then add another one (wideband) (I already have 2 outputs on my system)

[corozin 0]

No real point in a wideband lamda unless you have a standalone ECU that can make use of the data.

[potatonet 0]

its for my AFR gauge, not to mention my probable up and coming stand alone,

 

the LC-1 is really the best decision I could think of, that and a wideband AFR, I believe I can use my standard AFR gauge by modifying the analog output with the supplied program.

 

will try that first...

 

but yeah widebands rock!

 

will probably keep the thing on the standard AFR till I pass 16 psi in the 2.0L G60

[JMC 0]

the LC-1 is really the best decision I could think of, that and a wideband AFR, I believe I can use my standard AFR gauge by modifying the analog output with the supplied program.

 

Yep, that should do the trick as I mentioned above as the output curves and voltages can be tweaked idependantly for the 2 outputs of the LC-1. That's what I'll be doing with mine. Of course you could just buy a gauge made for the LC-1 which is already setup for it (got one with mine and it was only about $80 more).

[Kevin Bacon 5]

The LC-1 / XD-16 combo is the one to get.

 

You can feed the XD-16 gauge directly (which also has calibration, data logging, resetting etc controls built in) from the LC-1, aswell as having 2 analog outputs. A 5V WB + a simulated 1V narrow band output.

 

You would feed the latter to your Digifant ECU. The ECU gets the 0-1V it needs, but with the benefit of wideband response (MUCH MUCH faster than narrow b) and AF range.

 

One thing though, if you put a wideband probe into your stock lambda exhaust port, make sure the bore is big enough for a wideband sensor as it's a lot bigger than narrow band.

 

In the case of WB, air fuel ratio is not air fuel ratio :lol: Sounds daft, but you have to tell the LC-1 what AF you want for a given lambda voltage, say, 0V = 8AF and 5V = 20AF. Or even 0V=10AF and 5V = 16AF, the choice is yours.

 

The lambda voltage is lambda voltage though, and some folk work from just that, but some people don't want to read as low as 8AF, so can rescale the AFs accordingly.....quite nifty really! Narrow band is nothing like as flexible!

 

And this stoich thing....ignore it.....that's stoich in lab conditions. Engines actually run better on the richer side of stoich and is where most tuners aim to get the AFs.

[potatonet 0]

Engines actually run better on the richer side of stoich and is where most tuners aim to get the AFs.

 

 

thats why I dont even run an O2 sensor right now (was running it that way, till I ate 2 exhaust valves)

 

going back to my 02 sensor ways soon....

 

BTW how do I make my motor richer or leaner? Co pot? I never had to adjust it before... but with 2.0L and more boost and ported head it should be a little different, right?