A/F ratio guage? Why so Lean?

[turbomopar87]

I hooked up my auto meter cobalt A/F ration guage today and there is a good cahnce i may have done something wrong, but maybe its not me. The guage is saying lean at idle, and NEVER moves, not when reved, not when drived, not anything. I even adjusted the fule pressure up to almost 60 psi and it never moved, i had smoke out the exhaust from it being so rich and the guage didnt move. (I have +40's too)

Heres how i have it hooked up...(87 shelby Z TII)

~White wire- spiced into the white wire that lights up my coolant temp guage.
~Black wire- Ground. Battery ground to be exact.
~Red wire- Power, hooked it up right to the battery(not staying there)
~Purple wire- Goes the the MIDDLE wire on the O2 sensor, its a 3wire O2

thanks
kris

[slasky]

It goes to the black wire on the o2 sensor. I am not sure if it is the middle or not.

[turbomopar87]

i think there were 2 black wires on the 3wire O2...not definate though. I will check to see exactly which one it is tomaro.

[turbomopar87]

i looked today..and guess what..its on the middle wire, which is White...i am guessing this is wrong?

So i am going to hook it up on the black one....its safe to do this after the O2 connector right, like in the wires harness...i can just follow the black line on the O2 harness, through the relay, and then up to the corresonding wire right? Just wanna make sure before i splice agian.

[fuforums]

Check with a meter for continuity. That relay may change colors on the other side of it. Any reason you dont' want to use it on the harness closer to the O2 sensor?

[turbomopar87]

Check with a meter for continuity. That relay may change colors on the other side of it. Any reason you dont' want to use it on the harness closer to the O2 sensor?

Well i found out on TD.com that i AM spliced into the wrong wire. so i will put it up correct tomaro.

thanks everyone

as for not having it close to the O2...i dont feel like taking it off AGAIN, and its hard to reach back there to splice a wire, so i just wanna do it were i can reach easy. Maybe i will just take it out though, so i can put the spliced wire back together correctly.

[turbomopar87]

moved it to the black wire, perfect readings! :thumb:

so for future reference...1987 mopar 3-wire O2 sensor uses black wire for signal to A/F guage.

someone should do some reserch, and make a good FAQ on the different O2 sensors and how to hook them to A/F guages. I am sure it would be helpful to alot of people when they go to install their guages.