Bosch Oxygen (O2) sensors require a clean reference-air supply to operate correctly. This reference air is drawn through the gaps between the wire strands inside the sensor’s lead wires. Soldering blocks these air channels and traps contaminants, preventing the sensor from receiving the reference air it needs. This can cause incorrect readings, slow response, or premature sensor failure. SmartLink™ uses Posi-Lock® connectors to maintain proper airflow while still providing a secure, solder-free electrical connection.