When servicing an oxygen sensor, exercise special care as it has a permanently attached pigtail and electrical connector that cannot be removed; any damage to these components will ruin the sensor. It is important to keep grease, dirt, and other contaminants away from both the electrical connector and the sensor itself, and cleaning solvents should never be used on the sensor. Additionally, avoid dropping or roughly handling the sensor. Due to its installation in the exhaust manifold or
Catalytic Converter, which contract when cool, loosening the sensor may be difficult when the engine is cold; therefore, it is advisable to start and run the engine briefly before attempting removal, taking care to avoid burns. The sensors are located at the inlet and outlet of each primary catalytic converter, with two heated oxygen sensors positioned at the outlet of each exhaust manifold before and after each catalytic converter. For V6 models, raising the vehicle and securing it on jackstands may facilitate access, even for front lower sensors. Remove any components that obstruct access to the sensor, as these can vary by year and installed options, and in some models, primary oxygen sensors may be accessible through holes. Disconnect the sensor pigtail and carefully unscrew the sensor using an oxygen sensor socket or a large wrench, as special sockets are available at most auto parts stores. Installation follows the reverse order of removal, ensuring to coat the threads of the oxygen sensor with anti-seize compound and tighten it to the specified torque.