C.O. Adjustment Screw
Digifant CO Adjustment Screw:
The CO Adjustment Screw is located on top of the air flow sensor and can only be reached or adjusted after removing the anti-tampering plug in the top of the air flow sensor housing. This small plug is removed by drilling a 3/32 in. (2.5 mm) hole in the top of the plug and threading a screw into the plug so it can be extracted with pliers.
With the plug removed adjustment is made using a 5 mm hex wrench. Turning the CO Adjustment Screw clockwise makes the mixture richer (higher % CO). Turning the CO Adjustment Screw counter-clockwise makes the mixture leaner (lower % CO).