Forget The O2 Sensor!!!!!!!!!

[Schrade]

WAY BAD CALL 94JIMMY!!!
A finely tuned motor does NOT even use the O2 sensor. A finely tuned motor uses all of the O2 which gets burned in the combustion process, and the O2 sensor does no work. A poorly tuned motor lets O2 get through the combustion process (by not burning it all), and into the exhaust, and the O2 sensor tells the ECM that compensation is necessary to fix another problem. If you'd like to see that in print, I'll be happy to get it to you. A bad O2 sensor is an extremely common myth!!!

[Tangent]

Uhh, no fuel injected engine ever runs at the exact perfect mixture constantly. It is always swinging from rich to lean. When it's rich the O2 sensor reports that and the ECU leans the mixture, the O2 sensor reports that causing the mixture to be adjusted again, and so on... Ever wonder why Air/Fuel ratio gauges swing back and forth? (See pic below) The only time any engine will have a steady signal from an O2 sensor will be when it's either carbureted (non-feedback type) or when it's running in open-loop mode.

Note: Most cars will have a wider range than this illustration shows

[rksnc]

Boy has that guy got it all wrong. It is a good thing you don't work on cars for a living. Yea show me what you have. Oh yea read this while you are looking.

Main > Auto > ShortStuff

How does the oxygen sensor in a car work?


Shop for Does The Oxygen Sensor In A Car Work?


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.

[blazee]

Originally Posted by cbec1999

WAY BAD CALL 94JIMMY!!!
A finely tuned motor does NOT even use the O2 sensor. A finely tuned motor uses all of the O2 which gets burned in the combustion process, and the O2 sensor does no work. A poorly tuned motor lets O2 get through the combustion process (by not burning it all), and into the exhaust, and the O2 sensor tells the ECM that compensation is necessary to fix another problem. If you'd like to see that in print, I'll be happy to get it to you. A bad O2 sensor is an extremely common myth!!!

You are completely wrong. The object of this forum is to help people. In the past 2 days you have posted more nonsense than we usually see in a month. You should consider yourself lucky, the moderator seems to be MIA, otherwise you would have a temporary ban. Posting duplicate threads is a no-no. you have done that 6 times that I have seen. Starting a thread just to tell someone they are wrong is another no-no. Starting more than one thread for the same problem is another no-no. Reviving old threads is bad forum etiquette. If you try not to be such a tool, people will be more likely to try to help you in your other threads.

Originally Posted by rksnc

Boy has that guy got it all wrong. It is a good thing you don't work on cars for a living. Yea show me what you have. Oh yea read this while you are looking.

Main > Auto > ShortStuff

How does the oxygen sensor in a car work?


Shop for Does The Oxygen Sensor In A Car Work?


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.

Absolutely correct.

[Schrade]

I'm workin' on the article upload, or a link to the original site.

In the meantime, I must quote Steve Buscemi in Armaggedon - "God, it sucks knowin' everything..."

Well, I dont know everything. But I know a lot. And I know ignorance really is frustrating.

I got the help I came here lookin' for. And I've tried to return a little of the favor. Not a problem. You can't help everybody.