Ask Honest John

Honest John Ask Honest John » Whether forecast?

Whether forecast?

Can you say what type of air condition makes a petrol/diesel engine more efficient? Cold air, warm, damp, dry - all variables that might affect fuel consumption but I never hear any mention of it. I can well imagine that an all-electric car might be affected by excessive humidity or extreme cold.

Asked on 10 September 2011 by PW, Colne

Answered by Honest John
In the winter my FIAT 500 1.2 petrol does 48 - 49mpg. In the summer in dry weather it does 55 - 56mpg. This sort of difference has been experienced by readers with diesel cars too. Yes, cold will affect the battery range of an electric car, and using the electric heater (no heat from the engine) reduces its range by about 50%.

Real MPG enables you to register the fuel economy you are actually getting against your make and model of car, its engine and type of transmission.

Every time you enter an average consumption figure against your car, the overall average automatically adjusts to reflect it.

Real MPG

Cold-snap snow-how: Advice on coping with the freezing weather, including videos, facts and winter driving advice.

Honest John's Guide To Winter Tyres
Similar questions
I have the new Skoda Karoq 1.0 DSG. It's a lovely little car that drives well, even the DSG is amazing. However, I've done around 1200 miles and I can't get above 30mpg. The dealer said it's going to get...
Why is my fuel economy 7mpg less in winter? Since the weather has got colder, my fuel economy has got a lot worse. From an average of 43mpg in summer, I’m now only getting 36mpg. Apparently it shouldn’t...
Why do summer and winter mpg figures vary?