How to Replace the O2 Sensor on a 1995 Ford Ranger 4.0

The O2 sensor on your 1995 Ford Ranger measures the amount of oxygen expelled from its 4.0 engine. The amount of O2 affects the amount of gas the Ranger's computer sends to the combustion chamber. If the O2 sensor fails to work properly, the engine will idle and run rough. This could cause engine damage if left untreated. Replacing the O2 sensor is a relatively straightforward job.

• 1

  Locate the O2 sensor between the catalytic converter and the exhaust manifold on the passenger's side of the motor. The sensor looks like a spark plug and has a wire extending out of it.

• 2

  Follow the wire from the O2 sensor to the wiring harness. Unplug the O2 sensor from the wiring harness.

• 3

  Remove the O2 sensor from the exhaust pipe with a wrench, turning it counterclockwise.

• 4

  Thread the new O2 sensor into the bung on the exhaust pipe with your fingers then tighten it with the wrench.

• 5

  Plug the wire extending from the new O2 sensor into the wiring harness.