Volvo 850 96’er series 10V automatic: runs only in P position round

Hello in the round, I have the following problem with my petrol engine: it runs normally in idle mode. As soon as it is under train, it only takes on weak gas. WITHOUT rucksacks or detonators. Meanwhile, it hardly drives and almost goes out (except in P-position). Now it has been standing in the workshop for a month. The car master told me today that the moose in “S” mode is almost normal. I don’t see any more. Maybe an error in the automatic transmission. It does not light up a indicator light. it has been renewed in recent years: knock sensors have been changed last week cam-welve sensor has been changed Termostat has been changed spark plugs and cables have been changed Distribution box has been changed Petrol pump has been changed Do you have advice for me? Thank you in advance! Micha