After 100,000 miles, the oxygen sensor in your Ford Contour is probably ready to be replaced. However, it is technically possible to clean this part--though not recommended because it may shorten its service life. An oxygen sensor is a device on your vehicle that measures the emissions being released after going through the catalytic converter. It sends information to the Contour's ECU so that adjustments can be made for optimum fuel efficiency. Over time, carbon can build up on the sensor and cause it to malfunction. When this happens, and you want to know how to clean it, you'll have to learn how to clean a Ford Contour oxygen sensor.
Place the floor jack underneath the front jack point on the Ford Contour. This is located behind the radiator and is an extension of the frame.
Jack up on the Ford. Place a jack stand under each of the front pinch welds. There are two of them--one under each of the front doors. Then, lower the Contour onto the jack stands.
Disconnect the cable running to the negative battery terminal. Turn the retaining nut on the cable clamp counterclockwise to loosen it until the clamp can be pulled off the terminal.
Unplug the wiring from the O2 housing.
Remove the O2 sensor from the exhaust system using an O2 removal tool.
Hold the oxygen sensor with vice grips and heat the sensor end of the oxygen sensor with a propane torch until the tip turns slightly red. Do not let the tip "glow," but rather turn a light shade of red.
Submerge the heated end of the sensor into a bucket of cold water. Do not submerge the entire sensor, just the heated area. This heating and rapid cooling will cause the interior of the sensor unit to expand and quickly contract. It is the only real way to loosen the carbon deposits that have built up on the inside of the sensor.
Repeat steps 6 and 7 two more times.
Reinstall the O2 sensor and lower the Contour to the ground.
