Repair And Fix it

Oxygen sensors, commonly called O2 sensors, are a vital component in maximizing fuel efficiency in vehicles.

Name

An oxygen molecule consists of two atoms of oxygen bound together. Thus, O2 ers to the chemical formula for pure oxygen.

Task

O2 sensors monitor how much unburned oxygen is present in the exhaust from an automobile engine. The amount of oxygen indicates how efficiently the engine is burning fuel.

Effect

The cars computer uses readings from the oxygen sensor to adjust the mixture of air and fuel in the engines combustion chambers for maximum efficiency.

Location

There is an O2 sensor inside the exhaust manifold. Vehicles produced after 1995 also have a "downstream" sensor to measure the exhaust as it leaves the catalytic converter, to ensure that the converter is working properly, too.

Malfunction

Symptoms of a malfunctioning O2 sensor include declining gas mileage, rough idling and engine surges or hesitation. A vehicles "check engine" light will often come one.

Oxygen sensors measure the amount of oxygen in your cars fuel system when considered in conjunction with other components. The sensors are in the exhaust system and allow electronic fuel injection and emission control technologies to exist. The sensor sends details about the concentration of oxygen in the exhaust emissions and the signal will trigger an adjustment for extra oxygen or extra fuel. Maintaining working oxygen sensors is important not only to your vehicles health but also the health of the environment.

Instructions

Upstream oxygen sensor

1

Turn on the car and run for one to two minutes to expand the exhaust pipes enough for easier removal of the sensor. Locate the upstream oxygen sensor on the front end of the exhaust pipe behind the manifold flange and near the catalyst. If the vehicle has a V8, the sensor will be located on the rear end of the manifold near the flange for the exhaust pipe.

2

Unplug the electrical connector from the sensor. Remove the sensor mounting nuts with an appropriately sized wrench or ratchet. Finally, remove the sensor and gasket. Discard the sensor, gasket and nut.

3

Apply anti-seize compound to the threads of the new sensor. Using the new gasket, replace the sensor being careful not to contaminate and damage the surface with dirt or grease. Tighten the sensor into place using the replacement nut.

Downstream oxygen sensor

4

Locate the downstream oxygen sensor behind the rear catalytic converter (for all 2001 and later model) or behind the single catalytic converter (for 2000 models) in the exhaust pipes. If the vehicle is equipped with a V8, the sensor will be upstream of the converter in each exhaust pipe.

5

Unplug the electrical connector from the sensor. Remove the sensor mounting nuts with an appropriately sized wrench or ratchet. If the vehicle has a heat shield, remove it as well. Finally, remove the sensor and gasket. Discard the sensor, gasket and nut.

6

Apply anti-seize compound to the threads of the new sensor. Using the new gasket, replace the sensor being careful not to contaminate and damage the surface with dirt or grease. Tighten the sensor into place using the replacement nut.

The Chevrolet Metro was manufactured from 1998 to 2001. The car is equipped with two oxygen sensors, which are upstream and downstream of the catalytic converter. A failed oxygen sensor increases the amount of fuel burned by the cars engine, decreasing your gas mileage and costing you substantially more at the pump. Save the needless expense by replacing the sensors as soon as you discover the problem.

Instructions

1

Start the engine of the Metro. Let the car idle until the engine reaches operating temperature. When the temperature gauge reaches the point where it commonly runs, turn the engine off.

2

Raise the car with a jack. Position jack stands under the car. Remove the jack when the car is supported on the stands. Locate the sensors on either side of the catalytic converter.

3

Disconnect the electrical connection by pulling it apart. Remove the sensor with a wrench. Install the new oxygen sensor by hand. Tighten it with a wrench. Push the wiring harness connection back together until it clicks.

4

Repeat the process on the second sensor if needed. Raise the car slightly to remove the jack stands. Lower it to the ground.