O2 content of Air

[JanGeo]

Anyone wonder why I get good mileage on country roads that maybe it is because there is more oxygen in the air near the trees and no cars ahead of me burning it up making the air fuel mixture leaner and more efficient??? What do yo think?

[Compaq888]

or maybe because there are less cars/idiots on the road over there. If I would of lived in the country all of my tanks would of been 35+mpg. I always get a mob of cars behind me in the city, doesn't matter if my tranny shifts at 1500 or 2000rpm. I actually had to make the tranny shift at 4000rpm just to keep up with some soccer moms. 4000rpm might be okay on some hondas, but on a nissan 4000rpm is hauling ***.

[mtbiker278]

If anything there would be less polution in the air. No clue on how that would affect FE. I'm not sure about higher oxygen content though. It's possible, but you're O2 sensor should read any change.

[n0rt0npr0]

I notice countryside breezes are noticibly more humid than city breezes. More humidity=less air mass to try to move through.

Also the country roads in my area are significantly better in every way. Less traffic = less weear and tear AND country road construction is normally not time restrained nor rushed like city road construction = higher quality road = less rolling resistance =)
~Will

[JanGeo]

Yeah the roads are a lot smoother for sure - the O2 concentration I wonder if the computer corrects with an error or corrects exactly i.e. if there is less O2 then a little less gas and more O2 a little more gas but not enough to burn with the right amount of O2 that it is trying to burn at. I know I always seem to get better mileage on these particular roads but it may be the constant speed at 35-40mph that yields the better efficiency. My xB seems to do a lot better on the MPG when started warm instead of cold too.