Mitsubishi Montero Sport fails smog check due to exhaust issues on Mitsubishi Montero Sport

Some Mitsubishi Montero Sport owners report experiencing smog check failures due to various exhaust issues. Common causes include faulty oxygen sensors, which can lead to incorrect air-fuel mixtures and increased emissions, often resolved by replacing the sensor. Additionally, some owners face problems with failing catalytic converters that necessitate replacement to meet emission standards. Leaks in the EVAP system can also contribute to high hydrocarbon emissions, and repairing these leaks is crucial for passing the smog test. Issues with the Exhaust Gas Recirculation (EGR) system may further complicate matters, requiring checks and repairs to ensure proper valve operation. Lastly, incomplete emission monitors can result in failures; completing a full drive cycle may be necessary to prepare the vehicle for testing. Addressing these specific issues is essential for compliance with emissions regulations and successfully passing the smog check.