AoA,
Commando
Dear normally diesel engines make problems in winter because it has heater in its engines try to replace them and it will be ok.
I had a Jeep with 2C engine it use o do the same in winter so i changed all six heater they are not expensive if you go to any good diesel mechanic he would know about them.
Because diesel engine needs a little heat before you could start the car when these thing doent work properly your car will have trouble while starting.
Thankyou
Max