Question about 1996 Cadillac Eldorado

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Dedecting which co2 sensor might be bad?

When I start my eldo the check engine lite comes and the pead out says SEVICE EMISSICNS SYSTEMS and read out with scanner says CO2 sensor,so do I need to replace all sensors or can I start with a specific one first and which one might it be? is there one that seems to go before the other 3, because what I see on this site that there is 4 of them altogther.Can I clean them or do you have to replace them only?Please any help at all would be very helpful. Is there any way to tell which co2 sensor is bad?

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Neither... just because the code is setting does not mean that the O2 sensors are bad

instead it means that the exhaust is too rich or too lean

rarely, and I mean very rarely, like 1 in 100, will replacing an O2 sensor resolve an O2 code

seek an experienced driveability tech that understands the theory of O2 and fuel trims

most of the time the cause is an intake vacuum leak, leaking injector, or valve-train issues

Posted on May 06, 2010


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the less costly fixes include replacement of the o2 sensor and EGR valve i would not clean the EGR I would buy a new one there are very cheap you can pick these up at any local parts store .
also run some injector cleaner through your car at least a full tank of gas and one bottle of injector cleaner should be ran through.
you can also have your timing checked for a relatively low price.
and when you go into to have the vehicle checked make sure the car is been running because your cat convertor has to be warm in order to preform at it peak so do not do it when the car is cold.
all of the above are pretty reasonable fixes the general rule of thumb when you work on your own vehicle is start with the cheapest fix first then go on to the next.

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