LPG, Bio Diesel, Hydrogen, Fuel Cell Questions and Answers last answered over 2 years ago.
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add 5to10% white spirit or turps, this thins the oil and gives it a higher ignition point thus easier starting, add a little injector cleaner every now and then keeps the injector tips clean and spray pattern correct, check your glow plugs are working have a beer
do you have a fuel pre-heater? That can hope. also, 'glow' the plgs a couple of times. double heating them can help too. I have a 1.9 TDi 90 golf running on veg and it doesnt like the cold weather with a lot of veg, its too thick to ingite when injected when cold.