You probably won't need to replace them all. If you get the vehicle plugged into a diagnostic system or an OBD2 scanner it will give you a trouble code, (A code with a P and 4 numbers after it). This will tell you which sensor is faulty. It will give you a 'Bank' number and a 'Sensor' number for the faulty sensor. This is a V6 engine so it will most likely have 4 O2 sensors. They are usually located in the exhaust system, before and after the catalytic converter, two each side. Sensor One is mounted in either the exhaust manifold or the first section of exhaust as it drops to go under the vehicle, (before the Catalytic Converter). Then Sensor Two is usually mounted after the Catalytic Converter under the vehicle.
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You probably won't need to replace them all. If you get the vehicle plugged into a diagnostic system or an OBD2 scanner it will give you a trouble code, (A code with a P and 4 numbers after it). This will tell you which sensor is faulty. It will give you a 'Bank' number and a 'Sensor' number for the faulty sensor.
This is a V6 engine so it will most likely have 4 O2 sensors. They are usually located in the exhaust system, before and after the catalytic converter, two each side.
Sensor One is mounted in either the exhaust manifold or the first section of exhaust as it drops to go under the vehicle, (before the Catalytic Converter). Then Sensor Two is usually mounted after the Catalytic Converter under the vehicle.