Quote:
Originally Posted by Frank Lee
The difference in warm-up time between heater control cold or heater hot can't be much, can it? And after the engine is warm I don't see how heater control knob position can affect mpg at all.  However I can see a negative mpg effect from the alternator load increasing with higher blower settings. |
Actually you'd be surprised at the difference it can make, both from amp draw and from additional cooling via heater core. I've experienced both during below freezing commutes, fortunately the weather has been a bit more mild the past couple weeks and I have been able to get by with a jacket and no car heat.