02 sensors on 2002 kia optima 4 cyl
That depends on what the code says, sensor 1 is the manifold unit sensor 2 is the aft of the catalytic converter. But it sometimes is not the sensor that is bad, unmetered air leaks, dirty MAF, vacuum leaks, needing a tune up, low fuel delivery, just a lot of things need checked to be sure, a lot of people make the mistake of just throwing parts on a rig in hope they inadvertently fix the problem only in the end to find it was something simple like a bad sensor ground.
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