The oxygen sensors (also called O2 sensors) are one of the most important elements of the modern fuel injection systems. A finely tuned fuel injection system with an oxygen sensor can maintain an air/fuel ratio within a close tolerance of .02 percent. Keeping the engine at the stoichiometric ratio (14.7:1 air/fuel ratio) helps the engine generate the most power with the least amount of emissions.

There are a few signs that your oxygen sensor may be failing. In general, it is difficult to diagnose problems with the sensor, unless all of the other components in the fuel injection system have been checked and determined to be operating correctly. Some of the symptoms of a failed oxygen sensor system are:

• Irregular idle during warm-up
• Irregular idle with warm engine
• Engine will not accelerate and backfires
• Poor engine performance
• Fuel consumption is high
• Driving performance is weak
• CO concentration at idle is too high or too low
• Check Engine Lamp is illuminated

We offer Genuine Mercedes-Benz and Bosch oxygen sensors. To shop for your specific application, click here and enter your vehicle’s year.

We have installed O2 sensors on a M104 engine and documented with instructions. Let us know if you have questions or would like install instructions.

Get your O2 sensors today!