How You Can Replace the Upstream O2 Oxygen Sensor on Your 2001–2004 Chrysler Sebring with a 2.7L Engine

You should have a diagnostic check done when your car starts to idle roughly, when you start to use more gas than normal, or when the check-engine light comes on in the car. A diagnostic check can be done at many local auto-parts stores with a handheld device. The personnel at the store can explain what the problem is by looking at the codes and listening to the issues you are having with the car. In some cases, all you need to do is replace the upstream O2 sensor to get the car running well again. This is usually a simple procedure that most car owners can do themselves. Here is how you can replace the upstream O2 sensor on your 2001–2004 Chrysler Sebring with a 2.7L engine.

Upstream O2 Sensor Location

Open the hood and look straight down into the car's engine compartment. The upstream O2 sensor is located on the exhaust system between the valve cover on the engine and the radiator.

Bad-Sensor Removal

The wire connector for the O2 sensor sits right up along the valve cover. Follow the wires from the O2 sensor to the harness and unclip it. To unclip the harness, press up on the little tab in the front of the harness and pull the harness apart.

You should purchase an O2 sensor socket and some penetrating oil while you are at the auto-parts store. The O2 socket fits on the sensor without damaging the wires attached to it. The sensor will usually be frozen into position, and the sensor will be hard to unscrew so you can remove it. Spray the sensor down with penetrating oil and let it sit for about 5–20 minutes. Place the O2 sensor socket on a ratchet with an 8–10 inch extension and turn it counterclockwise.

If you still find it hard to turn the O2 sensor after saturating it with penetrating oil, put a breaker bar on the handle on the ratchet to give you extra leverage to turn the sensor. A breaker bar can be a piece of pipe about a foot long that can slide over the handle of the ratchet. Loosen and remove the O2 sensor.

Installation of a New Sensor

Set the new sensor into the slot and tighten. You want to tighten the sensor enough that it is snug. Reconnect the wire harness and close the hood.

Take the Sebring out for a long drive so the computer cycles through its checklist to make sure the new O2 sensor works well. The drive-cycle process will usually take about 15–20 minutes to complete under normal city driving conditions before the check-engine light turns off.

Take your car to an automotive shop for professional help.