ASSISTANCE ETS lights / Drezahl falls off / brake kicks takes no gas!

Hello together, I am in despair my Volvo C70 2001 t5 2.3 liter spins since yesterday. Error code is displayed nixht. During the switching process the power suddenly falls into the basement. If I give gas in idle mode on 3000 revolutions and then the brake kicks he takes no more gas and falls off on stand gas. In other forums it read what it could have to do with the air mass meter or the gas pedal adjustment. Someone had something like this before? With diagnosis device all errors deleted Ets goes out but after start of the engine again and the game starts from the beginning. I would be grateful if someone here already had some ideas about it before. Had it just in reperature and was afraid to grab it deep into the bag again. For tips I am really very grateful.