Air/Fuel Mixture: Testing and Inspection

Air / Fuel Mixture

CO Content (A/F Mixture) and Idle Speed cannot be adjusted, only checked.

- CO Content is checked upstream of the Three-Way Catalytic Converter (TWC).
- The Heated Oxygen Sensor (HO2S) must be connected during measurement.
- A/C must be switched OFF during measurement.
- Engine must be fully warmed up.
- Automatic transmission: Gear selector lever must be in PARK during measurement.
- EVAP-valve plugged.


CO Content 0.2 - 1.0%