O2 sensor locations on exhaust system upstream and downstream of catalytic converter (450/451/452/454).

Diagram showing O2 sensor positions on smart car exhaust with numbered callouts and removal procedure steps.

View full-size image ↗

See all Powertrain figures for the Fortwo (450), or browse the full figure library. Part numbers and callouts are community-sourced and cross-referenced against the manuals — confirm with your VIN before ordering.