hey another thing I just thought of, if you are show lean readings and the chip is adding fuel and ur still showing lean, check your exhaust and your intake adaptor for leaks if you have a leak before the sensor it will read lean no matter how much fuel the computer throws at it, and when the computer adds all that fuel it will run like crap, I pushed that o ring on the turbo adapter out and thats exactly what my car did, ran rough was showing lean o2's and the chip was adding all kinds of fuel.