Mazda3 1.6L Front and Rear Oxygen Sensor Z601-18-861 Z602-18-861 Original Factory Standard

When your Mazda3 1.6L MIL, idle irregularity, noticeably higher fuel consumption, or weak acceleration occur, usually the front and rear oxygen sensors have aged or failed, failing to monitor exhaust oxygen content accurately. Proper operation requires the sensors to feed ECU with air-fuel ratio data to maintain optimal combustion efficiency, ensuring power and emission standards. OEM: Z601-18-861 (front) and Z602-18-861 (rear); fits Mazda3 1.6L. Install with a dedicated socket to avoid over-tightening damaging threads, and ensure sensor harness does not contact exhaust pipe or moving parts to prevent short circuits or wear.