It Still Runs is the go-to destination for all things cars. From motors to radiators and everything in between, we've got you covered.

x

How to Bypass the Rear O2 Sensor

by Alibaster Smith

The O2 sensor in your vehicle gathers information about the emissions that are being put out by your vehicle. This information is sent from the O2 sensor to the vehicle's on-board diagnostic computer. If you want to tune your vehicle's performance, the secondary, rear or "downstream" O2 sensor may present a problem. To get around this, you can bypass the rear O2 sensor by generating a false sensor reading using a dummy O2 sensor.

Step 1

Jack up the front of your vehicle using the floor jack. Jack up on the front jack point located behind the radiator.

Step 2

Place a jack stand under each of the front pinch welds and lower the vehicle onto the stands.

Step 3

Climb under the vehicle and locate the rear O2 sensor.

Step 4

Unplug the electrical connector from the O2 sensor.

Step 5

Remove the O2 sensor using the O2 sensor removal tool and a socket wrench. Turn the O2 sensor counterclockwise with the wrench to remove it from the exhaust.

Step 6

Thread and tighten the new dummy O2 sensor using the socket wrench and O2 sensor tool.

Step 7

Then connect the electrical leads. By replacing the real O2 sensor with a dummy O2 sensor, your vehicle's engine control unit will be fooled by the sensor and will not generate any error codes for the vehicle's emissions control system.

Lower the vehicle to the ground.

Tips

  • Dummy O2 sensors are used for tuning vehicles that will not be used on public roads. They are made for a variety of vehicles. You will need to locate the dummy O2 sensor from an aftermarket supplier for your vehicle on the Internet or a mechanic that specializes in aftermarket racing or performance parts.
  • For specific information about your vehicle's O2 sensor and emissions control system, consult the particular vehicle's manual (see Resources).

Items you will need

  • Jack
  • Jack stands
  • O2 sensor removal tool
  • Socket wrench
  • Dummy O2 sensor

More Articles