While attending to an oxygen sensor, do it carefully because the sensor is situated in the exhaust system and the exhaust system contracts when it is cold; hence, tightening when the car engine is cold. To preserve the sensor and the threads used to install it, you need to let the engine run for a minute or two then turn it off not forgetting the heat might burn you. The new oxygen sensor is supplied with a permanently attached pigtail and electrical connector that must not be disconnected from the sensor, as it is explained in next page; because such action will affect its performance. Avoid contact of grease, dirt or any other form of contamination to the electrical connector and the louvered end of the sensor, it is must not be cleaned with any form of solvents. Be careful with the sensor not to drop it or be rude to it and also make sure that the silicone boot is well placed to avoid melting and to enable the sensor to function as expected. For the upstream oxygen sensor that is hard coded to the exhaust manifold for 2007 and 2008 models with the connector for the second sensor behind the washer reservoir with the second sensor mounted on the top of the warm-up
Catalytic Converter for 2009 and later models with the second sensor is mounted above the warm up catalytic converter, securely jack up the front of the vehicle on jack stands for the early models or remove the cowl cover Remove the upstream oxygen sensor electrical connector, this is located near the shift cable for the earlier models and between the cylinder head and firewall for the later models; also disconnect the sensor wiring harness from any clips. Remove the sensor with an oxygen sensor socket if available, and if reusing the old sensor put some anti-seize compound on the threads; the new sensor will contain anti-seize. Installation is done in the reverse sequence so that the sensor is tightened up to the stipulated torque. As for the downstream oxygen sensor, which is located only on the catalytic converter, securely raise the car on the jackstands and if you are working with the 2007 or 2008 model, remove the center console to unplug the connector, or with the 2009 and later models, trace the wiring harness up to find the connector to pull off. Remove the sensor using an oxygen sensor socket if any and apply anti seize compound if you're replacing the old sensor and reverse the sequence in case of installation but tighten the sensor to the recommended torque.