2004 Honda Accord
 

I have a 2004 2.4L Accord that the check engine light is telling me I have a bad O2 sensor. Is this something that can be easily changed, or is this a mechanic/dealer thing. I see from the parts catalog that there are 2 of them is one more likely to go bad then the other.

Thanks

i've only dealt with o2 sensors once on my last car. i changed the header and had to relocate one of the sensors to behind the cat. it's something that you can do yourself very easily. you just disconnect the wires and unscrew the sensor out. (proper tools required)

can't tell you which one takes more abuse though...

I'm pretty sure that on OBD2 cars (post '96) one sensor is in the exhaust prior to the catalytic convertor and one is post cat. I think the pre-cat one is more likely to go bad...unless you did something to screw up the cat and the second one doesn't like what it sees...but that's unlikely in car as new as 2004 unless you've been running leaded gasoline.

Since it's made to be somewhat easily replaceable, once you locate where the sensor is screwed into the exhaust it shouldn't be hard to find where the wires terminate and then remove and replace.

They can be tough to get out but if you buy the tool, it makes the job much easier. Replace them both, if one is bad, the other won't be far behind.