Rick Ohnsman
Active Member
In my '03 ST XLT it typically have the ventilation control set to bring in outside air, sometimes just through the upper vents, other times through the upper and floor vents, using the selector switch for that. (These are not the AC, or Max AC settings). However, I see that on the temperature setting dial there is a "blue zone" and a "red zone." It seems like even if I'm in the vent modes that if I turn the temp gauge into the blue zone, the air is colder than what I would expect if this were just outside air. Is the AC (or heat) coming on in these zones even if I'm not in one of the AC modes? Is the compressor running (and hence I'm hurting fuel economy?) With the price of fuel, I'm anxious to wring every drop for maximum efficiency. Right now I'm only getting between 14 and 15 mpg in normal in-town driving.