C5 2.0 HDI 136 PS jerks – no error message

Hello, help, my C5 2.0 HDI, 195000 km starts to spin! When you start driving easy and short jerking on the 1 course, then several jerking on the 2 and 3 course and later on the 4,5 ,6 course easy stalling and swinging while driving.As if it was again and again quite lightly brake and give gas. Up to now no control light went on and no error message available. He does not smoke! Has anyone had such a thing??? Gruss Josefsky