a/f gauge help

[gutted1]

I bought a a/f gauge from my friend a while back and hooked it up with I don't know what gauge wires. It reads so lean at idle that some times its not even lit. Is this normal? I have an safc 2 and running a little rich, whats the deal?

[im_slow!]

an a/f gauge is pretty useless unless you have a wideband. since your is off the chart at idle, im going to assume that you're using the stock 02 sensor. basically all you're getting is ball park a/f ratios with a cool light show.

[gutted1]

Thats what I thought. I went to Car z, and he was recomending the aem. But i'm a broke ass, and won't be able to get that till next Christmas.

[ryanman]

Actually the only thing an a/f gauge is good for is a light show, unless it's a w/b.

[Enthalpy]

If you have an unheated narrowband (1 wire) sensor, then it isn't hot enough to give you meaningful readings at idle. It will read lean as a result, and that's totally independant of what your actual AFR is.

If it's heated (4 wire), then you might be only a tad lean. Narrowband O2 sensors can be thought of as a switch. It tells you that you are rich or lean of stoich, but it doesn't tell you by how much you are lean/rich.

When the thing flashes back and forth, you are in closed-loop and the ECU is using it switching properties to stay right around 14.7 indicated AFR.

I'm assuming you don't have a stock wideband (5 wire).

[gutted1]

No w/b. I was at the boneyard yesterday and was going to get a one wire O2 off of something but did't have a wrench big enuff on me. I did score a Snap On pry bar though.

[Steve_C]

Some wideband kits have a narrowband output that you can use to accurately light up that display. PLX Devices makes several models that have that output

[Weston]

Some wideband kits have a narrowband output that you can use to accurately light up that display. PLX Devices makes several models that have that output

That really isn't much different the stock narrowband O2 sensor... the voltage vs A/F ratio plot is still the same, so it still only has precision where the narrowband sensor does. You really need to use the display that comes with the wideband sensor and controller. The narrowband emulation feature is only useful for connecting it to the ECU so that you can just replace stock O2 sensor with the wideband without pissing the ECU off.