A/F Gauge Signal Wire??

Hooked up my A/F gauge today, but I'm wondering if I might of tapped into the wrong wire for a signal.
@ idle, and cruising on the hwy under no load, only the last 3 "Stoich" LEDs light up and the first 4 "Rich" LEDs light up all at the same time.
@ light boost, and full boost only the very last "Rich" LED lights up. None of the "lean" LEDs or the first part of the "Stoich" LEDs have lit up.....although they do all work for about 1 second when I turn the key off.
Does this sound normal??? It doesn't to me.
The wire I used is the orange wire from the O2 sensor wiring harness. I tapped into it down by the ECU......#115 on the 15 pin connector.
I read somewhere someone used the shielded wire from the O2 sensor harness under the hood. Is this where I should of tapped into??? How do I test to figure out which of the three wires from the O2 sensor is the signal wire and not the heater, or ground wires???
Any help would be great.

:confused: :dontknow: Anyone.....I know there are some members that have installed A/F gauges :wall:

How many DC volts should the signal wire read?? Mine is reading .855v at idle. Shouldn't it be lower than that at idle?

the middle wire on the connector of the o2 sensor is the signal wire... you should have readings of .5-.99v roughly....hmm i'll call ya tonight to discus this

The middle wire is the shielded one....right? Which terminal is this @ the ECU?
I've tried all three wires with no luck, and I'm starting to think I may have a faulty gauge.

i get some strange signals from my a/f as well. i can get almost all of the lights lit up at idle/lot throttle. the signal gets stronger with more throttle and usually ends up oscillating from lean to the end of stoich and back again. i go solid rich (2 bars lit) when on boost at mid rpm and actually go lean (yes, LEAN!) at high rpm. i have some fuelling issues.

i tapped into both the ecu wire and direct to the o2. same signal. it didn't make a difference as to which one. the age of your o2 sensor will also make a difference.

The O2 sensor is new with only about 600 miles on it. I'll test drive it tomorrow with it hooked up to the middle shielded wire and see what I get.
At idle with it hooked up this way I only get the first 2 lean leds and nothing else.
Same if I hook it up to the black/red wire.
If I hook it up to the 3rd wire...the orange one, the last 3 of the Stoich, and first 3 of the rich leds light up and nothing else.

Hey LOOK@@@ i can help
I got an a/f to when i firsat turn my car on it stays on stoich when it warms up it goes to lean and then no lights at all
Then when i lightly tuch teh pedal my lights go fromlean to the end or middle of stoich.
Your o2 sensor works along with the TPS so i would check that out and dotn worry aboiut teh lean deal
if u were seriously running lean at hi rpm your motor would of been tost by now

Guys, as far as I know, they bounce all over the place until you go into closed loop (or was it open loop? I never can get those two straight), which is usually WOT, and then they stay steady.

So at idle they will act weird. Makes sense.

Looks like I got it figured out :mike: Turns out the cheap splice thing I bought wasn't allowing for a good contact to the signal wire. I re-wired it directly, connecting it to the middle insulated wire on the ECU side of the O2 sensor in the engine bay (Thanks Bart), and now it seems to be functioning like it's suppose to.
Now at idle it bounces back and forth from lean, stoich, and rich....and looks like Knight Rider. From everything I have read this is how it's suppose to do in "closed loop".
I still need to take it on the road and see if it locks in like it's suppose to in "open loop"

i have myne connected directly to the o2 senso then a splice for the connector wire:dontknow: