You don't say if you garage your C-Max Hybrid...? If you are leaving it outside in 0° to 32° weather, it WILL immediately start the gas engine when you turn they key on. A layman will know this is happening because you will audibly hear the engine kick in immediately. As you know, the Ford C-Max Hybrid starts silently under normal (not severe) conditions. Remember, without all the fancy terms, this car is always seeking to find the best fuel mix between high voltage batteries and gasoline. Also, the real time MPG rating is automatically averaging between the use of gas, HV batteries and power returned through braking. A good way to see this is to choose a trip odometer and zero it out when you start up. In that weather, for a while you will be lucky if it climbs higher than 10 MPG. I've seen it as low as 4 MPG in sub freezing weather. At that moment of startup, it's drawing 100% gas. The positive news is that it also immediately starts sending a charge to the high voltage batteries. I tested my 2014 Ford C-Max Hybrid SE during freezing weather one morning, on a five mile run to the grocery store, over roads that are slightly rolling, with both my house and the store at about the same altitude (so one is not "uphill" from the other). On the trip TO the store, I hit 14 MPG. On the trip home a few minutes later, I hit 28 MPG. Here is the other factor: I was running my heater full-force all the time. I also avoided rapid acceleration while braking conservatively (no short, hard stopping). Your personal driving habits will greatly affect your MPG. Of course, most of us love the way these babies accelerate so quickly, and if you've learned to brake without caution, you will likely continue that habit unless you consciously work to change it. For that reason, I keep my display set at "engage", to see braking, gas and HV batteries usage. On a road trip from Nashville to the Jacksonville, Florida area (during warm weather) and returning to Nashville, I averaged 42 MPG for the trip, using cruise control whenever possible and still also running the A.C. during the whole trip. On a warm day, my round trip to my local grocery store averages 56 MPG, as opposed to those numbers I quoted in freezing weather. This Fall, I was doing a lot of moving, using very poor driving habits, and I had 34 MPG (leadfoot numbers). Cheers!
