Engine jerks and goes off when it’s warm

Hello guys, the day before yesterday I bought a Volvo V70 with 144 hp and 270,000 km. During the test drive everything was fine and on the way home it happened. The engine started to jerk and stutter, then also during the gear change until he finally strangled himself. I would like to say that this happened every time you wanted to give a little faster gas (especially during gear change). I then drove into a workshop and let me install new spark plugs and the master briefly checked the ignition if everything runs as it has to run. And it was like that. Now I stopped and drove back to the dealer with a very tame foot again. His workshop master today checked half the day where it can lie. All contacts cleaned up, the ignition hoses, distribution cap and fingers. A call at Volvo directly was pulled through, however we did not get to drive with my Swedes time out of time because as soon as the engine is warm he already said goodbye. He should check the throttle caps but can not give me the dealer workshop master 😉 Well there the condition is not too cold there for me.