HomeAll RepliesReply To: Strange Noise from Venting System or Motor Reply To: Strange Noise from Venting System or Motor Sponsored November 26, 2019 at 10:02 am #577919 SLYDOGParticipant My 97 Park Avenue heater vent actuator would make noise sometimes when switching from AC to heater. Sponsored Subscribe to GM Authority For around-the-clock GM news coverage We'll send you one email per day with the latest GM news. It's totally free. First Name Last Name Email Address Subscribe via Email Leave this field empty if you're human: Sponsored