What is the 2003 Toyota Sienna bank 1 sensor 1 location?

The 2003 Toyota Sienna bank 1 sensor 1 is located on the side of the motor that the number one cylinder is on and before the cat. The number one cylinder is on the backside of the motor (the side closest to the firewall). The O2 sensor will be in the exhaust pipe near the exhaust manifold. Some symptoms that You might be experiencing are higher than normal fuel consumption and excessive smoke coming from Your exhaust. The oxygen sensor in Your vehicle measures oxygen levels in the exhaust gases exiting the engine. The oxygen sensor should be replaced every 60,000 to 90,000 miles. This sensor is a wear item and does fail over time.