V40 1.8 – Engine stutters / jerks at low speed

Hello, for a long time I have had the problem with my Volvo V40 1.8l 115ps Bj. 98, 300000km, that the engine stutters or jerks during acceleration in the lower speed range up to 3000rpm (as one should call it). The problem especially occurs when I push the accelerator a little bit more through. It seems to me as if it is swallowing itself. In the cold state, right after the start, the problem does NOT occur, only after approx. 500m – 1km goes off. The V40 has been converted to gas since 200000km, the problem occurs in gas operation, as well as in petrol operation – no difference. I have already renewed ignition coils, ignition cables, ignition plugs, without change. The oil is clean, the cooling water is also clean, neither great water nor oil consumption. Was at Volvo to read out the fault memory, has cost 35€ and allegedly found no faults. (Allegingly I don’t trust them at all, they can give me a break again. But the problem is not like Krüben?