Question to those who have wired up an Air/Fuel ratio gauge. Where did you run the wire too??? I'm thinking you could splice into one of the wires on the back of the PCM But I dont know which color(s) to use. I want to wire it in so I can select between the front O2 and the rear O2. Just dont know where to hook it up. Could someone please help....

 

Splice it into the violet wire coming from your front O2 sensor.

 

The terminals for the front O2 sensor signal wires are C20 purple/white (Bank 1) and C8 purple (Bank 2). Connector "C" is the gray or clear connector. You can use a single pole, double throw switch to allow you to read either side.

Just curious.... why would you want to read the rear O2 sensor?

 

I think he might mean the left front o2 and the right front o2???

 

Sorry I did type that up wrong, I ment to say Right front O2 and Left front O2. I found a purple/white coming out of the terminal labeled red or blue I forgot which one it was. How can I find what purple to use? I counted 3 or 4 of them. Just one more thing. Where can I get a nicely layed out diagram labeling all the wires running into the PCM? Just FYO my PCM is an OBD2, Thanks again,
-Paul

 

PCM pinout

I did mine to the Clear/gray plug...#8