how do o2 sensors work?
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Prowlin' with a Purpose
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how do o2 sensors work?
ok, so someone told me that if i was getting a check engine light due to the rear o2 sensor going off or something like that, that i should get another o2 sensor that was made for the front and put it in the back.. he said that this should correct the CEL.. now if this is true, this leads me to believe that o2 sensors have something built in so that if the o2 level reaches a certain point, it sends a signal to the ecu and the check engine light turns on... if this is the case, than this option would work because then the acceptable 02 levels from the engine are still the same acceptable levels when the pass the second sensor.. when in a testpipe or something
is this true?
is this true?
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From: Zulu Alpha Tango Foxtrot
Rep Power: 311 They work by taking in exhaust gas. The oxygen sensor is a small fuel cell. Everytime an oxygen molecule enters the sensor, it goes through a membrane and bonds with another molecule or element to create a free electron. Now imagine this at a much higher / faster level.
Essentially it is a 0 to 1 mA (or something like that) output to your ECU. It will constantly send a mA signal back to your ECU. Your ECU is what determines what is an unacceptable voltage (ie through a lookup table what is an unacceptable amount of oxygen in your exhaust stream) and adjust the fuel mixture to alleviate the deviation. If the sensor is out of whack - like sending more than 1 mA or will not calibrate properly (I believe the ECU will test them on startup) than it will turn on the check engine light.
Funny things about oxygen sensors - they are always on. Unless you have them in an oxygen depleated environment, they will always generate energy until it fails.
Essentially it is a 0 to 1 mA (or something like that) output to your ECU. It will constantly send a mA signal back to your ECU. Your ECU is what determines what is an unacceptable voltage (ie through a lookup table what is an unacceptable amount of oxygen in your exhaust stream) and adjust the fuel mixture to alleviate the deviation. If the sensor is out of whack - like sending more than 1 mA or will not calibrate properly (I believe the ECU will test them on startup) than it will turn on the check engine light.
Funny things about oxygen sensors - they are always on. Unless you have them in an oxygen depleated environment, they will always generate energy until it fails.
Originally posted by maxsin
Honda programs the check engine light to come on after so many miles . look in the manual and it shows you how to turn it off, that is if there is no problem with your car.
Honda programs the check engine light to come on after so many miles . look in the manual and it shows you how to turn it off, that is if there is no problem with your car.
lol thanks for ur N00bie Answer..
we were all n00bs at once right? at the least i do know how to use the search button! 
Ricerus Maximus
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Rep Power: 332 That sounds like it would work, try replacing it with the same sensor that is on the front. Of course this could be an ECU problem. If the ECU has it's voltage limitations set differently to set the check engine light to on then you won't get it to work. If the ECU is programmed to accept .02ma from the front sensor and .05ma from the rear sensor then swapping out the sensor won't work because the rear O2 sensor will still be off because it's not sending the required .05ma, it's sending something else. Am I being understandable? Let me know if this needs more explaining.
(all numbers were made up off of the top of my head)
OBD II is a biyatch
(all numbers were made up off of the top of my head)
OBD II is a biyatch
Originally posted by clownprince
That sounds like it would work, try replacing it with the same sensor that is on the front. Of course this could be an ECU problem. If the ECU has it's voltage limitations set differently to set the check engine light to on then you won't get it to work. If the ECU is programmed to accept .02ma from the front sensor and .05ma from the rear sensor then swapping out the sensor won't work because the rear O2 sensor will still be off because it's not sending the required .05ma, it's sending something else. Am I being understandable? Let me know if this needs more explaining.
(all numbers were made up off of the top of my head)
OBD II is a biyatch
That sounds like it would work, try replacing it with the same sensor that is on the front. Of course this could be an ECU problem. If the ECU has it's voltage limitations set differently to set the check engine light to on then you won't get it to work. If the ECU is programmed to accept .02ma from the front sensor and .05ma from the rear sensor then swapping out the sensor won't work because the rear O2 sensor will still be off because it's not sending the required .05ma, it's sending something else. Am I being understandable? Let me know if this needs more explaining.
(all numbers were made up off of the top of my head)
OBD II is a biyatch
yea i was thinking bout that too... also .. ud have to cut the connector off and replace it with the old one(the second one) so that it will fit into the plug.. cause im pretty sure their different plugs..
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From: so cal djmota=oscar
Rep Power: 323 that would be intersting if it works. but you have got to wiegh the cost of a new O2 sensor with that of an O2 simulator....is it worth the trouble. just a little food for thought.
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