O2 sensor's relationship to "Check Engine" light...?

Question

Dumb check engine light is on in my 2001 Nissan Altima... pretty sure its the obligatory O2 sensor. If I just pull the fuse for the O2 sensor do you think that might kill the light?

Actually - I DID find a dedicated fuse for the sensor... but yes, you're probably correct.

Answer 1

The very first thing I would try is to make sure that your gas tank cover is on securely. A loose gas tank cover is a simple cause that activates the CHECK ENGINE light.

The CHECK ENGINE light should generate a hard error code or a soft error code that is stored in your vehicles computer memory. If the CHECK ENGINE light is always on, then it is a hard code and that could be a serious problem that needs immediate attention. If the light is sometimes on then off, then on, that is a soft code and is not as serious.

You can try to reset the CHECK ENGINE light by pulling and replacing the fuse. Or try disconnecting then reconnecting the battery. However, this will not work for all vehicles.

You can try to obtain the error code that the engine computer generates when the CHECK ENGINE light comes on. Supposedly AutoZone will do this for free. Then all you need is to determine what that code means. Ask at AutoZone. Or try telephoning a local dealer or post the code on the internet in an auto repair forum.

Good luck.

Answer 2

It will not only NOT kill the light, but would probably cause your Altima to go into 'limp mode', since a needed input from the O2 sensor is not reaching the engine control computer.

Sorry, but there's no way around this one, other than replacing that defective sensor, if that's the case. (Don't feel badly. One of my cars has FOUR of those O2 sensors.)

Answer 3

You can't "just pull the fuse" because the O2 sensor doesn't have a dedicated fuse. You have no choice other than replacing it but before you do that make sure - not "pretty sure" but actually sure - that this is THE problem because check engine light is an indication of one or more of various emissions control component(s) being out of wack, and replacing them based on assumption will unlikely make you happy.

Answer 4

There is no definitive answer, but for six weeks of moderate driving, long term damage is unlikely. Increased fuel consumption may occur with a failed oxygen sensor if your car inherently runs rich, meaning the fuel system is flowing more than necessary to run at optimal condtions (stoichiometric air/fuel ratio). However, if it runs lean, then you are actually saving fuel, but the exhaust components (exhaust valves, exhaust A-pipe, catalytic converter) will run hotter. If this is allowed uncorrected long-term, you will damage these components, usually with the catalytic converter. To give a background to the above, the O2 sensor indicates the amount of oxygen flow in your exhaust. The engine computer uses it to regulate how much fuel should be injected. If the sensor indicates that the exhaust gas oxygen content is too high (lean), it will inject more fuel than its base fuel maps. If the oxygen content is too low (rich), it will subtract fuel from its base fuel maps. Furthermore, each car is different. One can physically run rich (more fuel than necessary, unless the O2 sensor and engine computer) correct it. In this case, fuel consumption is higher. The opposite can occur, when it is lean. Anyway, it is good that you are getting it fixed soon, but you probably didn't hurt your car.

Answer 5

Maybe the light but I think the on board diagnotics will still show the sensor which is a problem at inspection in many places

Answer 6

Auto Zone will check system for free, and will tell which sensor to replace.

Answer 7

no...........the o2 sensor is an integrated part of your computerized system & must be in place to run properly.....if it,s burned out or defective it must be replaced.....have your system scaned for problem,s before making any repair,s. ..good luck.