Bad O2's causing poor mpg?
 

Well ive been told that bad oxygen sensors will result in poor fuel economy, my car just rolled over 95k, is it time to replace the o2's? im getting approx 15 mpg city and like 19 mpg highway. btw its a stock geared camed ls1 with stock tune...

Do you have after market long tubed headers? If so, run down to your nearest Advance Auto Parts, Autozone or NAPA and pickup some Bosch #13111 oxygen sensors. They are sch-weet. :)

At the moment its on stock manis, ill try them... :judge:

I had an O2 disconnected (hilbilly at the exhaust shop moved it and never reconnected), and then along the way had a misfire in #8 cylinder... got like 12mpg over half a tank.

Well, if you don't have longtubes, then I believe the Bosch part # for stock manifolds is #13444. Basically part #13111 is for the C5 Corvette, but their really nice for f-body owners who have long tubes because no o2 extensions are needed so #13111 works out nicely. Unless your planning for long tubes in the near future, I wouldn't get #13111 because it will hang loose and you don't want that. Just my 2 cents.

If you have a stock tune on a cammed motor then theres your problem. 02's are only going to be a minor part to the whole problem in general.

I bet he means stock cammed also--?? :confused:

If you have a cam in the car that REALLY isnt that bad of gas millage. Depending on your driving it could very well be what the car is getting b/c of the cam and whatnot. If not did you tune the car up... fuel filter, PCV vavle, air filter, exc all these things can have an effect on your gas millage and kill performance