Hey I have a 1985 320i german spec. when I start it in the morning everithing is ok, until I accelerate it, it losses power and does accelerate correctly. when it warms up it runs ok again. I might have problems with the air flow meter. I never idles correctly. it has a black track tha´s no longer that black, any ideas? that track is the one that gets the electricity to open the avlve inside the air flow. need help!!!!