Should I replace O2 Sensors?

[StealthSonic]

Hi, this month has been a horrible month for my 2000 Accord LX 4cy. I have to do a smog check in order to get my Aug 2005 sticker, but I took my car to several places and they refuse to smog test my car.

One is because I have engine check light on. I paid a guy at the gas station 120bucks to find out the error codes. It appears that I have to things that are wrong and they all related to O2 Sensors.

The mechanic then told me I should get 2 new sensors because my Accord has 2 O2 sensors, one at the manifold and another one is in the catalytic converter. But the mechanic can't promise me that my car will pass smog check if I get those sensors replaced... I was like, okay...?

Two, I have a OBX headers on, and according to the OBX factory, it's CARB exempt, but it doesn't say it on anywhere on the header itself... So the mechanic can't promise me anything... eventhough I have stock catalytic converter.

I really like to narrow down problem, should I start off by getting 2 sensors first? or should I do something else? Too bad I don't have the original manifold anymore.

Oh I forgot to mention that my car runs exellent, gets good milage on gas (about 350miles/tank on local/hwy), no powerloss, runs very smooth and I can hardly smell any smog that is coming out of the tailpipe.

[scubawrstlr]

Yea replace the O2 sensors. Its not a bad idea to change em every so often anyhow. Other than that I donno what to say. I live in Wisconsin where emmisions are not a factor.