The mechanics say my O2 sensor needs to be replaced, is it a big deal?

Question

I have a 2001 Chevy Tracker. What does the O2 sensor do and does it effect performance/gas mileage? Is it expensive to replace? Do you have any suggestions? Can I replace it myself? What does anyone know about this?

Answer 1

The O2 sensor measures the amount of oxygen left in the exhaust after combustion, (not a CO2 sensor, it measures oxygen only!, that's why it is called an oxygen sensor). Unlike what some of the other posters may think, it is an important part of the engine management system and cannot be simply unplugged, you will see reduced miles per gallon and performance without it. The O2 sensor is the main input to the engine computer to determine how much fuel the engine should receive, just as the mass air flow sensor tells the computer how much air is going into the engine. By measuring the amount of oxygen in the exhaust the O2 sensor can tell whether the engine is rich or lean and help provide the correct fuel mixture. You can change it yourself if you can get to it with a regular 7/8 in. wrench, or purchase an O2 sensor tool from a local parts store.

Answer 2

You should have your O2 sensor replace because you call will not be able to monitor certain engine performances. It isn't a "major" thing to replace right away, but if your car is going for inspection, then you need to have it replace. Here is what I got on O2 sensor. Also the link below is going to have EXACTLY what i told you PLUS the price of how much an O2 sensor cost (usually under $100). Now add that amount to what labor cost and I say you may pay roughly (lets say 2 hours at 65 per hour 130 labor, 70 parts = $200). Maybe less.

Every new car, and most cars produced after 1980, have an oxygen sensor. The sensor is part of the emissions control system and feeds data to the engine management computer. The goal of the sensor is to help the engine run as efficiently as possible and also to produce as few emissions as possible.

A gasoline engine burns gasoline in the presence of oxygen (see How Car Engines Work for complete details). It turns out that there is a particular ratio of air and gasoline that is "perfect," and that ratio is 14.7:1 (different fuels have different perfect ratios -- the ratio depends on the amount of hydrogen and carbon found in a given amount of fuel). If there is less air than this perfect ratio, then there will be fuel left over after combustion. This is called a rich mixture. Rich mixtures are bad because the unburned fuel creates pollution. If there is more air than this perfect ratio, then there is excess oxygen. This is called a lean mixture. A lean mixture tends to produce more nitrogen-oxide pollutants, and, in some cases, it can cause poor performance and even engine damage.

The oxygen sensor is positioned in the exhaust pipe and can detect rich and lean mixtures. The mechanism in most sensors involves a chemical reaction that generates a voltage (see the patents below for details). The engine's computer looks at the voltage to determine if the mixture is rich or lean, and adjusts the amount of fuel entering the engine accordingly.

The reason why the engine needs the oxygen sensor is because the amount of oxygen that the engine can pull in depends on all sorts of things, such as the altitude, the temperature of the air, the temperature of the engine, the barometric pressure, the load on the engine, etc.

When the oxygen sensor fails, the computer can no longer sense the air/fuel ratio, so it ends up guessing. Your car performs poorly and uses more fuel than it needs to.

Answer 3

This is something you can do your self. I am not sure how many Oxygen sensors your tracker has but you can easyly find out asking the dealership or looking at your exaust sytem. If you shop around you can find an Oxygen sensor for as little as 12dollars or as high as 60 dollars. The main purpose of the Oxygen sensor is to determine how much of a calibrated substance such as carbondioxide your vehicle is releasing on every exaust reading and the engines computer adjust to ither more air less fuel, or more fuel less air to meet emission requirements. Multiple Oxygen sensors are present in vehicles now days to maintain more acuracy when the engine adjusts and are located at various parts of the exaust system. Some are just by the exhaust manifold, on the exaust manifold, catalitic converter, somewhere in the pipe from the exaust manifold to the catatilic converter. If equiped with a turbo just before enter the turbo and so on.

Answer 4

This Site Might Help You.

RE:
The mechanics say my O2
sensor needs to be replaced, is it
a big deal?
I have a 2001 Chevy Tracker. What does the O2 sensor do and does it effect performance/gas mileage? Is it expensive to replace? Do you have any suggestions? Can I replace it myself? What does anyone know about this?

Answer 5

O2 sensors is part of the vehicles emission system. I believe it measures the quality of combustion. In many cars they are easy to replace but on others they are a bear. If you have easy access (normally located in the exhaust manifold between the engine and the catalytic converter) you can do the job yourself. There is a socket you can buy which is used specifically for O2 sensors. Disconnect the wiring, remove the sensor and screw in the new one and reconnect the wiring. Should work.

Answer 6

The O2 sensor is an emission part. It's like a spark plug that is usually in the exhaust manifold. It's not too hard to change out yourself and the part is usually around $60.

Answer 7

Your 02 sensor effects your gas mileage so it is definitely worth replacing. You probably have 2. it is usually near your catalytic converter or somewhere else along your exhaust system. It looks a lot like a big spark plug and is about as easy to replace.

Answer 8

it senses the amount of unburned fuel in the exhaust. replacement is not usually hard but sometimes requires a special socket to remove.
prices can run upwards of $100 for the sensor.
your vehicle has 2-one before and one after the catalytic convertor

Answer 9

02 Sensor is for smogging the vehicle... the only problem it will cause is it wont pass smog with a bad 02 sensor... and your check engine light will remain on. It will not effect the drivability of your vehicle. good luck

Answer 10

it should not be hard may have more that 1 will help keep it running good just do it