I get about 16 MPG city driving. I used to get a little, more even after the EGR block off, and emission removal. I been studying my data logger, and notice that I do not get any O2 readings until about 2-2500rpm. I even tried a new O2 sensor, and that hasn't changed. I'm guessing the voltage supply for the warmer has failed somewhere. Someone told me without O2 readings at idle, its maxing out my fuel trim

So once I get a warmer day (40ish) I'm going to go around and try to figure it out. Cause its sucks to have to let your cars stay at idle for so long to warm up.
