The Toyota has oxygen sensors that will need repair work. Deciding which sensor is in need of serious replacement can be more exasperating than going under the vehicle and switching out the oxygen sensor. The sensors were built into the exhaust systems for the purpose of monitoring the oxygen level in the fuel. A high variance during operation may lead to diagnostic trouble codes. These will be spotted by the oxygen sensor, which will in turn set off the "check engine" light inside your vehicle.
Put a wheel chock behind one of the rear tires. Apply the parking brake.
Put on the goggles. Slide underneath the vehicle. Find the sensor you want to repair. They are set on the front exhaust pipe. It’s near the manifold and downstream on the exhaust system near the catalytic converter.
Don’t try to clean the oxygen sensor once it’s removed. Doing so can contaminate it, making it useless. Take out the nuts on the flange of the oxygen sensor. Take the vise grip pliers and squeeze with enough force to loosen the nuts. Un-thread the nut by hand.
Follow the oxygen sensor wire to the plug connection. Disconnect the wires by pressing on the clip lock. Use the screwdriver. Disconnect the plug. Take out the old sensor. Remove the old gasket from the oxygen sensor flange located on the exhaust pipe. Replace it with a new sensor.
Clean the threads using an 8-by-1.25-mm re-threader. Put the new gasket onto the flange. Place the new sensor into the porthole. Put the nuts and lock washers on the studs of the flange. Use a socket and ratchet to tighten. Now put the oxygen sensor wire back into the plug connection. Remove the wheel chock.
