Is there additive in diesel at this time of year to stop it freezing? Taxi wouldn't start this morning even though it was spinning over fast on the starter. Temp outside was -7C It spluttered a couple of times then just cut out. Put an electric fan heater underneath it for 1/2 hour, hand primed the fuel system and it started then no problems. I've been off work for 2 weeks so the fuel that was in it was put in 2 weeks ago when it wasn't as cold as it is now.