To install an air fuel gauge open the hood and look straight down the exhaust manifold. There is a plug with a bunch of wires going to it just under the header. That's your O2 sensor. Trace the wires back to the grey connector plug near the engine block and slide back the wire shroud so you can see the wires (4 of them). Put a tap splice on the BLACK wire between the O2 sensor and the connector.
. Run the wire inside the car and attach the wire you spliced into the O2 sensor to the purple wire on the back of the gauge. You then need to find the 12V and Ground. Hook up power and ground to their respective wires and that's it.
