I am assuming you are using diesel fuel and not an alternative fuel and that your idle speed is normal and not turned way down.
Ceck to see that your glow plugs and glow plug system is working properly.
After that worn injector nozzles, and Injection pump timing, valves needing adjustment all can paly a part in causing the problem.
But it would be nice to have more information. Dose your car start easily? When you start your car is it smoking and what color is the smoke. What color is the smoke while you are holding down the pedal and dose the smoke go away after the car is warmed up?
Dose the car idle smoothly after it is warmed up? How many miles are on your car? When was the last time your fuel filters were changed?

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84 300D, 82 Volvo 244Gl Diesel