VIDEO LIBRARY: ENGINE MANAGEMENT

How To Remove and Replace An Oxygen Sensor.

the oxygen sensor is one of many sensors in your car's engine management system all cars built since the early nineteen eighties have at least one some have two or more if an oxygen sensor malfunctions your car's performance and fuel economy will decline and it will generate excessive hydrocarbon emissions of Phil sensor can also damage the catalytic converter a costly emission system components replacing the oxygen sensor recommended intervals or when it is failed will keep your engine running at the correct calibration for best power and economy and save you money in the long run protecting the environment while saving money is a good thing so we can look at how to diagnose and replacean oxygen sensor right here right now welcome to the orders on D. I. Y. garage the oxygen sensor helps the vehicle's engine management computer determined correct fuel mixture by measuring the amount of oxygen in the exhaust a lot of oxygen indicates the engine is not getting enough fuel to burn very little oxygen in the exhaust means that the engine is getting too much fuel when the computer gets a signal from the oxygen sensor in the just the air fuel mixture to compensate there by maintaining a near perfect ratio if the computer doesn't get a signal from the sensor the car won't stop but it will not operate at peak performance or efficiency did you know a car with a malfunctioning oxygen sensor may seem okay but it will waste fuel water spewing greenhouse gases and other pollutants into the atmosphere because oxygen sensors live in a harsh environment they should be replaced at recommended animals even if they haven't failed sensors connected the wiring harness with wanting to wire should be replaced at twenty five thousand to thirty thousand miles three or four wire sensors have a life expectancy of about fifty five thousand to sixty thousand miles some four wire sensors can last up to a hundred thousand miles while sensors with five or six connecting wires are rated at a hundred and fifty thousand miles most cars built between nineteen eighty and nineteen ninety six and one oxygen sensor located between the exhaust manifold and the catalytic converter if your cars of that period and symptoms like excessive fuel use like a power and eliminated check engine light suggests the oxygen sensors failed it wouldn't hurt to replace it maintenance replacement is probably over do the job isn't difficult most cars built after nineteen ninety six have at least two sensors if the check engine light switches on and a car built after that date you can determine a failed oxygen sensor is the culprit I reading trouble code set in the on board diagnostic system with a code reader this tool which is available at auto zone will tell you which sensor has failed and because industry specifications for engine management diagnostics we're standardized in nineteen ninety six it will work on almost any later model car but read the operating manual before attempting to use to read the codes on the Ford fusion simply plug the code reader into the data link connector here on the driver's side if the car had a fill censor the code reader would indicate which sensor had failed and where it was located it would tell you if the culprit was cents or one which is always upstream of the catalytic converter or since our true which is always behind the convert for V. six and V. eight cars which can have as many as four oxygen sensors the code reader would indicate if the defective sensor was an engine bank one or bank to most vehicles have an oxygen sensor Ford of the catalytic converter and another one behind the converter here we'll use a section of exhausted holes an oxygen sensor to show you how easy it is to install a new unit using the right tools once you determine which sensor is defective you can remove it with this special oxygen sensor socket wrench which is available at auto zone because the sensor corrodes with the exhaust system it can be tough to loosen so scored some penetrating oil on the threads before attempting removal after attaching the socket to a three eight strive ratchet place it over the sensor and turn counterclockwise to remove it being careful not to damage the wires to install the new sensor remove the plastic cover and if the threats are not already coated with anti seize compound apply some but be careful to apply only to the threads contaminating the tip of the sensor can affect its performance you should also make sure doesn't bump up against the pipe when inserting it into the sensor mounting hole after **** the sensor down by hand tight knit to manufacture specs with the oxygen sensor socket mounted on a torque wrench then re attach the wiring and make sure it's rotted away from the exhaust as you say replacing an oxygen sensor is difficult and it's a job you shouldn't put off because a defective sensor will cause your card run poorly while spewing pollutants into the atmosphere for more details about oxygen sensor replacement or any other automotive service topic be sure to talk to the experts at auto zone remember parts are just part of what we do