Problem with my Volvo 850

Hello dear forum community, I have recently had a problem with my Volvo 850 and hope to get here the decided tip for troubleshooting. It’s a Volvo 850 lw 2.4 10v petroler 106kw. And he suddenly didn’t jump on after short distances. When turning around the key everything sounds quite normal, but he doesn’t come, when I have waited a while he went on again and drove again. However, the issue is getting sharper. Since I already knew this problem I started the car especially in idle mode on the weekend to avoid the problem, when driving off he started to stutter, went out and the same problem as if I had had had had it out!! Now I drove today towards a friend who wanted to look at the car, after about 2km when driving on a traffic light he went out again and no longer at! Does anyone have any advice about what problem it could be here? Thanks in advance, MfG Jan