I have one issue with my V8/ABH wich I can´t figure out. When standing still and pushing the throttle hard up and down between 1000 and 3000 rpm the response is not what expected, and the engine missfires quite often. But on higher revs(above 3000 rpm) the engine is a monster, without missfires. The sparkplugs are new and the car also passed the emissionstest at our swedish "TUV". Whats wrong? Any ideas? VAG-COM reports no errors.