You sure about that. My diesel cars have been and are much less fuel efficient until they are up to temperature. After all the oils are thicker and theres more friction when they are cold for a start.
-7 tonight, how low can diesel go?
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You sure about that. My diesel cars have been and are much less fuel efficient until they are up to temperature. After all the oils are thicker and theres more friction when they are cold for a start.
Thicker oil and reduction in efficiency when cold is common for both petrol and diesel. Diesels don't operate at as higher temperature as petrol, but still take longer to warm up. In reference to fuel added then there is fuel injection timing advance on a diesel during the cold.
MMI Car Menu > Heating > Use Aux Heater = Auto
Outside temp below 7, coolant cold, drivers side climate set to max heat, push and hold volume up and down buttons simultanously for 10 seconds, SID displays "heater" and the climate setting can then be changed. This works only when the Norse goddess of winter, Skaói, smiles upon you though
No engine is efficient until its up to temp, its rubbish saying that diesels are as efficient when cold and theres no drop in fuel consumption. They do run cooler than petrols but still need to run at their optimum temp for maximum fuel efficiency. Advancing the timing on a diesel when cold makes it run faster which in turn will make it use more fuel. After all your advancing the fuel pump not a spark ignition system like a petrol.
There loads of threads on BMWland about thermostats failing on the diesels the main sign is that fuel consumption goes right up because they are running cold. Theres about a 30-40% increase in fuel consumption when the stats are fully open and the engine cant get up to temp.