A bad oxygen sensor can make her Jeep operation rough and also exhibit a variety of unpleasant symptoms. Thankfully, instead of it is reasonably easy and inexpensive.

You are watching: 2004 jeep grand cherokee 02 sensor locations

This article uses to the Jeep cool Cherokee WJ (1999-2004).

Oxygen sensors measure up the oxygen content in the exhaust gasses exiting the engine. This measurement of oxygen is frequently referred come the "Air:Fuel ratio (AFR)," i m sorry is measured in components of oxygen to component of fuel gasses. The PCM (powertrain manage module) offers the inputs from these oxygen sensor to manage engine performance. If the AFR is either also rich (too lot fuel, i.e. 9:1 AFR) or as well lean (too much air, i.e. 16:1 AFR), then the computer needs to change other parameters come compensate. However, together these sensors wear and age, they can be at risk to coming to be unreliable, providing incorrect readings, or ceasing to provide readings every together, which causes engine performance to endure greatly. Usually speaking, if your oxygen sensors make it previous 100,000 miles, climate you"re a happy one. If her Jeep is about due, then take into consideration this great idea that preventative maintenance and also replace that old oxygen sensor.


Materials NeededNew O2 sensorWD-40, or equivalent liquid penetrating oilOxygen sensor wrench (can purchase or rental for totally free from numerous auto parts stores)Jack and also jack stands (optional, however makes it easier to gain under the car)

Step 1 – eliminate oxygen sensor

Before beginning, disconnect the battery. Then crawl underneath your Jeep ~ above the driver"s side. If necessary, you deserve to jack increase the former of the car and place the on jack stands if girlfriend don"t fit underneath while it is top top the ground. The O2 sensor is located on the exhaust pipe, close come the engine. Look at the catalytic converter and also follow it forward to find the sensor. On slide the oxygen sensor wrench end the sensor and also twist the counterclockwise come unscrew that from the pipe. Disconnect the harness linked to the sensor and also remove the sensor.

Figure 1. Locate the oxygen sensor.
Figure 2. Unscrew the oxygen sensor.
Figure 3. Disconnect and also remove harness.

Step 2 – Install brand-new oxygen sensor

Connect the wiring exploit to the brand-new oxygen sensor. Collection it in the exhaust pipe and also hand-tighten. Usage the oxygen sensor wrench to finish tightening the sensor until it is snug, yet not too tight. Reconnect the battery and also start the car.

See more: How Should One Of A Kind Be Hyphenated Adjectives, One Of A Kind

Figure 4. Download the brand-new oxygen sensor and also connect the wiring harness.

Featured Video: just how to change Oxygen Sensor