Hello! I am from Norway. I have a 1990 325ix touring, and I have problems with my climate control. I have changed som sensors, the watervalve ! And I changed the heater controll today (part Number 64 11 1*386*822). I have also checked a motor that control a Arm (that changes between hot and cold air) What happens is that if I turn the heater controll to hot, and rev the engine over 2000 rpm I can hear a knocking sound from the water valve. But if I am under 2000 rpm its working. But I can only choose max hot or cold. I really need help to figure out this problem!