Once the oxygen sensor on your 1995 E320 gets heated up from the exhaust, you will need to use protective gloves to keep from burning yourself. The oxygen sensor monitors the exhaust coming out of the engine. It then adjusts the air to fuel ratio to optimize fuel economy and horsepower. Oxygen sensors on your 1995 E320 will likely need to be replaced after 100,000 miles. Replacement oxygen sensors can be purchased from most auto parts stores.
Tools Used: Tools, Jack, Jack stands, Socket wrench, O2 sensor socket, Protective gloves
Replace Heated Oxygen Sensor
Put on protective gloves and jack up the front of the E320 using a floor jack under the front jack point behind the radiator. Place jack stands under the front pinch welds of the vehicle.
Lower the vehicle onto the jack stands.
Climb under the vehicle and locate the oxygen sensors on the exhaust. The oxygen sensors, or O2 sensors, are located before and after the catalytic converter towards the front of the vehicle. There is one before the converter and one after. The sensors look like small plugs sticking out of the exhaust piping.
Unplug the wiring from the O2 sensors.
Unbolt the O2 sensor from the exhaust using the O2 sensor socket and pull the sensor off of the exhaust.
Thread and tighten the O2 sensor, reconnect the electrical connector then lower the E320 to the ground.