HELP: Stock S15 running EXTREMELY lean

[Nicely]

I get 500+km from an average tank.

 

[ichi-go]

Once u tune it, mileage will definately be better as they usually lean it out abit for more power. Try changing your o2 sensor if you have bad mileage.

I get average 360km from a tank. Normally u would get 450 easy.