HELP!!! AIR/FUEL ???

[mazda20]

I am trying to hook up my gauge but i don't know which wire it is. I tried autometer but there was nothing online for my 94 mx-3 4cyl. Thanks in advance.

[OsoSlo z28]

pin 2N...gray/red wire

[mazda20]

I have the mechanical gauge and the instructions said I should hook it up past the O2 sensor where there are 3 wires, is the 2N wire somewhere else or am I looking in the wrong spot.

[OsoSlo z28]

to be honest..i don't know. i've never seen a mechanical a/f gauge. does yours have all the pretty lights on it? if so...then you want the wire right as it goes into the ecu. if not, then you'll have to grab the wire before it comes inside the cab of the car...but im not sure.

[mazda20]

autometer's directions said I should grab the wire before it comes inside the car so my choices are basically two black wires or a blue wire with a red stripe. I don't know either.

[OsoSlo z28]

looking back over my directions... "violet wire: connect to oxygen sensor signal wire. connect to vehicle wiring harness, not oxygen sensor since some oxygen sensors use shielded wire."

[mazda20]

I appreciate your help with this, but maybe this beyond me. I am looking in the alldata manual and on the web mx-3 manual and trying to figure out where the wiring harness is located. If the wire is shielded shouldn't it be difficult to see the wires out of the O2 sensor?<P>Should I just take it to a mechanic I don't want to screw up my car over something small like a guage?

[OsoSlo z28]

what's the model number for your gauge? does it have all the lights or does it have a needle? the wire you you have to hook up...is it violet? shielded can mean that it's covered so you can't see or that it has an extra layer of insulation due to it's location.

[mazda20]

It the phantom 5775 which is the one with all lights and it has the violet wire. The wires are at the connector after the O2 sensor comes out of the manifold and all these have are the plastic shielding I could splice right into those.

[OsoSlo z28]

ok..you have the same type i do...but i have the sport comp. it would just be easier to get the wire inside the car right before it hits the ecu. it doesn't really matter where you get it...it would just look cleaner to have it all behind the console instead of a little violet wire running into your engine compartment

[mazda20]

Okay that sounds good so the wiring harness and Pin 2N like you said earlier and this should be located under the dash on the passenger side.

[OsoSlo z28]

yeah....gray/red wire. how are you going to hook it up/splice it?

[mazda20]

Splice it and solder it in there then tape it back up and get out of there....

[OsoSlo z28]

are you going to just strip back some insulation in the middle of the wire or are you going to pull it out of the plug?

[mazda20]

You know they make those clips so I dont have to splice the wire. I could just clip on, I would probably try that first if that doesn't work I will go ahead and cut.