What is an Air/Fuel Ratio Gauge? An air–fuel ratio meter monitors the air–fuel ratio of an internal combustion engine . Also called air–fuel ratio gauge, air–fuel meter, or air–fuel gauge, it reads the voltage output of an oxygen sensor , sometimes also called AFR sensor or lambda sensor. How Air/Fuel Ratio Sensor Works Benefits of Installing an Air/Fuel Ratio Gauge Different Air/Fuel Ratio Gauges Available in the Market The One We Picked Tools Required for Installation Air/Fuel Ratio Gauge Installation Step-by-Step Tools: -Air/Fuel Gauge (I used an autometer sport) -1 wire 1 volt O2 sensor (narrowband Bosch) -Wire insulation -22mm Open End wrench -Extra 18gauge wire (any color) -PB Blaster (optional) -Wire taps (16-18 gauge) -Heat Shrink Tubing (Optional) -Zip Ties -Wire Crimper -Solder/Electric tape (or you could use those small red tubes that connect the wires together...ur choice) Step By Step 1: I didnt disconnect my battery so i just started o...