Ok a quick question... do o2 sensors have to be replaced at a certain milage ? My car has 120k on it and im not sure if its the original o2 sensors. The gas milage hasnt been that great lately, but i have no CELs or anything.

 

If they are original then it may be time to put in new ones but there are so many factors that can effect the gas milage it could be any thing just slightly out of tolerance causing it and still not throw a CEL or your CEL light could be burnt out look to see if it comes on when you go to start the vehicle

 

Yes it does.

 

Mine has 170k, and my o2 sensor it's still ok, however there are limitations, depending on how the car used to run, if it was running rich/lean for a while than most likely you have to replace it, i mean it does clean itself if car runs good. If you are getting crappy mpg, than change your fuel filter, check/change your spark plug/wires, and check your fuel filter. And don't floor it as much.

 

heres my nub question what the part # for the 2nd o2 sensor in 96 prelude vtec?

 

I don't know what it is but you don't need to know either if your at a place to buy it it will be looked up by application

 

I got some extra OEM o2 sensors for 5th gen Preludes. Not sure if they'll fit 4th gen VTEC's or not, though...


Modified by Urban Legend at 10:43 AM 2/1/2006

 

O2 sensors are good until they fail. How's that for a specific answer?

The only way to check them is to measure the output signal to see if they are still operating within spec. Certain contaminants will kill them really fast, or they could last 180,000 miles like mine did. As they fail, they get slow and lazy. Enough to effect idle and fuel efficiency, but not enough to trigger a CEL.

BTW, two generic Bosch sensors I tried weren't good enough. Ended up buying the Honda OEMs.