There are two O2 sensors for each bank of cylinders. The upstream O2 sensor is located closer to the engine, and the downstream O2 sensor is located further away from the engine.
To locate the O2 sensors for Bank 1, follow these steps:
1. Open the hood of your vehicle.
2. Locate the exhaust manifold for Bank 1. It is located on the front of the engine.
3. The O2 sensors will be located on the exhaust manifold. The upstream O2 sensor will be located closer to the engine, and the downstream O2 sensor will be located further away from the engine.
The O2 sensors for Bank 2 are located in the same location, but on the opposite side of the engine.
