Not so much of an issue on the injection cars but I can vouch for it getting cold enough for the cold air to make a difference as I have had issues with carb icing on both Grumbleweed and my old Y10. Round about freezing and damp is just right to leave the car gasping it's last then dying on the motorway. Leave it 10 mins it's right as rain again as the heat soaks up from the engine.