Farm Boy
they're all reactions
- Joined
- Sep 8, 2010
- Messages
- 26,985
Of course there a a number of other variables that are affected by temperature and will affect fuel mileage (from tire pressure to various fluid viscosities) in addition to AC use, which is probably the biggest decrease from when temperatures are lower. Though from what I understand cold temperatures are generally worse (particularly while various components warm up to their normal temperature) but there is probably a point where it reverses.
Most of the changes are probably pretty small on their own but combined I could see them having noticeable effects.
True. AC compressors generally takes enough of your engine's horsepower to run that it makes a noticeable difference. Ignoring that, rate of speed and how little slowing down and speeding up you have to do(ie traffic) is probably the biggest single impact. If you could accelerate slowly up to about 45 mph and stay there until you reach your destination that is generally about as good as most commuter cars are going to get for efficiency. If you are more excited about getting home at the end of the day and accelerate harder that will also make a difference even if your cruising speed remains the same. Btw, don't tailgate - aside from being terrifically unsafe the fact that you are following somebody closely means you are going to constantly be adjusting your speed to match theirs. Terribly inefficient to do all that slowing and accelerating.