O2 sensor

judge_roy
Not Active

Asked by judge_roy Feb 04, 2013 at 02:01 PM about the Volkswagen Jetta

Question type: Maintenance & Repair

We know that it measures the amount of oxygen, we just don't know which pnp npn functions this information will help? also, from my good friend Gary:What's an o2 sensor? and did you know that there are valuable metal in a catalytic converter and people steal them? ....like who 's gonna buy some nasty exhaust covered rare metal?  Take it to the jewelers?

7 Answers

7jimmy7
11,785

ahh. hello, why do you think platinum exceeded gold for the past 10 yrs on the metals market, it sure aint prettyier .and function is to aquire stichieo or whatever they call a perfect mix ratio like 14 to one air fuel for slow burn, that may have even changed by now with the crap they sell at the pumps these days, and the two sensors on the cat fr. and rear each have their own function

1 out of 1 people think this is helpful.
tenspeed
55,385

Scrap yards and eBayer's buy used catalytic converters. I do know that people steal them. I had one stolen from me.

1 out of 1 people think this is helpful.
Lars Cats
2,895

Lambda sensors, colloquially known as O2 sensors, make modern electronic fuel injection and emission control possible. They help determine, in real time, if the air–fuel ratio of a combustion engine is rich or lean. Since oxygen sensors are located in the exhaust stream, they do not directly measure the air or the fuel entering the engine. But when information from oxygen sensors is coupled with information from other sources, it can be used to indirectly determine the air-fuel ratio. Closed loop feedback-controlled fuel injection varies the fuel injector output according to real-time sensor data rather than operating with a predetermined (open-loop) fuel map, improving fuel consumption and lowering potentially harmful emissions.

6 out of 6 people think this is helpful.
Best Answer
Scott Sr.
2,745

And...the O2 sensor is also a bimetallic device with platinum which changes its voltage in the lambda circuit in relation to the ratio of oxygen in the exhaust stream relative to ambient oxygen levels. They have a limited life-span and must be replaced at regular intervals.

2 out of 2 people think this is helpful.
garageman
1,175

I will take Lars answer one step further,the O2 sensors job is very important to modern engine controls.The make up of the sensor consists of a zircon element,it was discovered many years ago that this element will produce a minute electrical current in the presence of oxygen,in the modern automobile this current is used by the engines management computer to vary the injectors cycle time to keep the mixture as close to "lambda" or the ideal mixture ratio of 14.7 to 1 that is the ideal fuel to air ratio for absolute complete combustion,using a mass air flow sensor ,or a Map sensor to determine engine loads,all of the components work together to keep the mixture at that ideal.When one or more of these components gets out pf sync .more than three times a trouble code is generated and the check engine lamp is triggered on. The catalytic converter uses the oxygen in the exhaust stream in combination with the platinum and other exotic elements in the ceramic element to convet the harmful gases into harmless co2 and water vapor,as any thing automotive it has a finite life,the rear O2 sensors job is to send a reading to the engines computer.where it is compared to the front sensor,too slow a response or if it is working almost the same as the front sensor is an indication that the converter is starting to lose it's efficiency,in an ideal world all work together to produce clean air from bad.Any variations will set the light,indicating service is required.

4 out of 4 people think this is helpful.
Scott Sr.
2,745

GO BOSCH!!!

3 out of 3 people think this is helpful.
garageman
1,175

Best bet is to go OE on sensors Bosch or Hitachi for Asian systems,and always get the correct ends,these universal sensors they sell ,unless they are installed absolutely the correct way.You will encounter problems,the voltages are so small that any interference by a poor electrical connection will create issues.

1 out of 1 people think this is helpful.

Your Answer

Add photo

Related Questions

Jetta
Looking for a Used Jetta in your area?
CarGurus has 38,511 nationwide Jetta listings starting at $1,200.
ZIP:

Search Volkswagen Jetta Questions

Volkswagen Jetta Experts

#1 Tom Demyan
Tom Demyan
Reputation 680
#1 Scott Sr.
Scott Sr.
Reputation 680
#3 grayj831
grayj831
Reputation 440
View All

Related Models For Sale

Used Volkswagen Passat"
492 Great Deals out of 27,711 listings starting at $1,495
Used Honda Civic"
938 Great Deals out of 59,982 listings starting at $999
Used Volkswagen Golf"
75 Great Deals out of 5,768 listings starting at $2,295
Used Volkswagen GTI"
107 Great Deals out of 4,903 listings starting at $2,500
Used Volkswagen Jetta SportWagen"
92 Great Deals out of 5,000 listings starting at $6,600
Used Honda Accord"
1,218 Great Deals out of 68,769 listings starting at $1,288
Used Volkswagen Beetle"
332 Great Deals out of 11,962 listings starting at $1,000
Used Toyota Camry"
1,344 Great Deals out of 73,151 listings starting at $1,490
Used Toyota Corolla"
1,048 Great Deals out of 59,416 listings starting at $1,300
Used BMW 3 Series"
1,320 Great Deals out of 38,023 listings starting at $1,988
Used Nissan Altima"
1,509 Great Deals out of 85,532 listings starting at $1,000
Used Audi A4"
333 Great Deals out of 11,374 listings starting at $1,795
Used Mazda MAZDA3"
585 Great Deals out of 31,359 listings starting at $1,900
Used Volkswagen CC"
197 Great Deals out of 5,108 listings starting at $7,995
Used Ford Mustang"
916 Great Deals out of 27,356 listings starting at $1,500