1999 Toyota Camry 2.2L Engine Code P1133 - Front O2 Sensor Replacement Guide

My 1999 Toyota Camry 2.2L engine light came on at 108,000 miles. After connecting a code scanner, I found the fault code P1133, which indicates a problem with the front oxygen sensor (Bank 1, Sensor 1) — located right at the exhaust manifold and easily identifiable. I replaced the oxygen sensor with a Bosch unit for approximately $200. During the days before receiving the new part, I drove normally and noticed only minor symptoms: slight loss of power and a small drop in fuel efficiency. After installation, I cycled the engine control system four times using the code scanner. The check engine light turned off, and the vehicle now runs smoothly. Additional notes: - The heat shield on the exhaust manifold must be removed during replacement; one bracket broke off during reassembly. I repaired it with an arc welder while the car was parked and disconnected the battery to avoid electrical issues. - Anti-seize compound is recommended for sensor installation — I didn’t have any, so I’ll use it next time. - The manufacturer recommends a torque of 35 ft/lbs; I don,”t have that tool, but I tightened the sensor securely by hand. This should be sufficient for safe operation. This repair has resolved the P1133 code and restored normal engine performance. Hope this helps others experiencing similar issues with their 1999 Camry 2.2L.