4Pcs 02 O2 Oxygen Sensor Up & Downstream for BMW 128I 335I 325I 328I

PRODUCT FEATURES 100% High quality brand new. 100% factory tested to meet or exceed all original equipment specifications. Quality components for proper fit and long-life performance. Each sensor has application specific design to ensure a perfect fit for easy installation. Q&A Q: Why does the oxygen sensor have false alarm, after installation ? A: The clearing of the errors can be obtained on most systems when the vehicle battery is disconnected for at least 60 seconds. The assignment of the new sensor parameters is done automatically when the errors are cleared, but in some systems a short adapting tour is required. In this case the vehicle has to be driven on the road for some 10-15 minutes, in order to have the ECU adapt itself to the new sensor. Q：How should I install oxygen sensor ? A: The following is the installation instructions: Use the correct part number as listed in the application catalogue ,Do not use sensor if i has been dropped ,Remove protectio