well, when I got my emissions test done 2 years ago one of the readings was high and they say it is because the O2 sensor was failing and dumping too much fuel into the engine! So, I figure I will swap them out....They did pull the codes when the check engine light is on, which is not all the time, and they said the O2 sensor was starting to fail. So, I am going to swap both out and see if it helps my gas mileage.
imcastock - In answer to you, I did replace the flex pipe because it was starting to crack.
Gas Mileage is about 425-450 KM per tank depending on how much highway and city driving I do. Car has 208,000kms on it and one of the lifters is also clicking. I mean, the gas mileage is not horrible, but I dont want to fail emissions in 2 months becuase of an O2 sensor!
[Edited by accentguru on Dec 13, 2005 9:01 AM]