Hi guys, I’ve been having a problem with my C70 2.4T Aut, MY05 for a few years, that in the 60 km/h range the speed drops to 1200U/min. The engine then buzzes naturally, it happens even when driving evenly, but can be reproduced well by light gas-giving. Usually this occurs when the car is half warm. At the cold start, the speed also drops to the normal 900U/min instead of running slightly higher. Thermostat has already been exchanged and various software replayed. I have now bought a Bosch air mass meter (after a cheap part led to the car barely running) and the whole thing has changed, but is still there. At least in idle he now turns higher and drives somehow softer. What do you think about it? I am grateful about every idea. Greeting Jens