How a Oxygen Sensor Works?

The oxygen sensor in your vehicle is an electronic component that is designed to measure levels of oxygen in the engine exhaust. Typically, the oxygen sensor is mounted to the exhaust system tube, with the sensor part inside the tube. This measures the oxygen mixture by generating a small amount of electricity due to the difference in atmosphere, oxygen and carbon dioxide. The PCM monitors this voltage and adjusts the fuel system and engine timing accordingly.

The oxygen sensor is in continuous communication with the engine control unit giving it the information necessary to adjust fuel intake and ignition timing for correct combustion. When the engine is cold the oxygen sensor is not as active, but will become so after the engine coolant has reached a specific temperature. Early sensors used this time to “heat” up so that the reactive material within could work properly, to correct this condition the oxygen sensor has been constructed with a 12 volt heater element. This heater allows the sensor to read at maximum efficiency quicker. When the throttle is wide open and under max load the oxygen sensor will go full voltage until normal operating conditions return. Typically changing an oxygen sensor when necessary is a simple process. Most solutions to oxygen sensor problems result in changing the oxygen sensor, but always be sure there are no vacuum leaks present in the intake
system, this can give a false oxygen sensor trouble code Due to the severe usage the sensor endures, it is common for most sensors to last approximately 75,000 miles, however it is not uncommon for an oxygen sensor to last only 40,000 miles depending on your driving habits and vehicle conditions.

Oxygen Sensor Cut Away

Over the life of the oxygen sensor soot build up can occur on the sensing probe which can result in inaccurate readings. This can cause your engine to run rough and consume excessive fuel. Remove the sensor and replace it with a new sensor.

How do I check An Engine Oxygen Sensor?

All engines run on an optimum fuel to air mixture called "stokiometric" which means chemically balanced. This balanced fuel to air ratio is 14.7 to 1, 14.7 parts air to 1 part fuel. The oxygen sensor is created using the active chemical such as zirconium, electrochemical (also known as Galvanic), infrared, ultrasonic and very recently laser. When a lean mixture code is detected by you or a technician the first tendency is to replace the oxygen sensor. The best way to check the operation of the sensor is to run a simple test. No matter if your engines
oxygen sensor has one wire or four there is only one sensing wire that feedbacks information to the PCM. To find this wire you will need a car repair manual. If a trouble code is present that pertains to an oxygen heater sensor failure, replace the sensor to repair the problem. An oxygen sensor must be warm before it will operate properly.

Warning: If a malfunction exists with related components such as an engine misfire or engine vacuum leak do not perform this test. The oxygen sensor is designed to operate within a particular range, if this range is exceeded the sensor will give the appearance that it has failed.

GM Oxygen Sensor - (appearances will vary)

Oxygen Sensor Test
Tools needed to perform these tests: Voltmeter

* Step 1 - Once the oxygen sensor sensing wire has been located connect a volt meter to the feedback wire and ground. Select the millivolt operation on the meter.

* Step 2 - Next, start and run the engine at idle until warm (about 15 minutes). Observe the voltmeter; it should bounce slightly at whatever voltage the sensor is centered at (about 150 millivolts).

* Step 3 - Continue to observe the meter and have a helper rap the throttle. The meter should drop for a split second as the mixture leans out in the first milliseconds of the throttle bore being opened. Then quickly rise for a spit second as the throttle closes and the mixture richens. The volt meter should stabilize at the original operating voltage when the engine returns to idle.

Performance Exhaust System

A performance exhaust system can be anything from a simple “cat-back” system to give you a little better sound to a full tuned set of headers to replace the restrictive exhaust manifolds. Always consult state and federal emissions laws before modifying your vehicles exhaust system.
Performance Exhaust

There have been numerous advances in the technology for performance exhaust systems. While standard exhaust systems are designed as cost efficient as possible, a performance system is usually made from a higher grade of material with a more performance-oriented design. The exact type of performance exhaust often varies depending upon the vehicle and application. Adding performance exhaust systems is easily handled with just a few tools and will boost performance immediately.

Inspect your exhaust system on occasion to ensure that there are no cracks, holes or rust. Only inspect the exhaust system after the engine has cooled down to avoid burns. When exhaust replacement is required a performance exhaust system might be a good consideration. After a new exhaust system has been installed it is normal for funny smells to be produced. This condition will stop once the exhaust system has been heated and cooled a few times. The reason for the smell is a new system is manufactured using oils and paint and until the impurities are burned off it will create an odor.