There's an old saying in engine tuning that when adjusting the mixture of your engine you can be too rich a bunch of times, but only too lean once. With that in mind, determining the air-fuel ratio ...

This is the basic Gunson CO tester. The 12-volt connections power the unit while the pulse pump draws exhaust gas into the analyzer. The unit is designed to measure CO exhaust percentages. Those ...

Why it matters: O2 sensors feed critical data to your ECU, helping maintain the ideal air-fuel ratio for performance, efficiency, and emissions control. Reading the signals: Healthy upstream sensors ...