Knocking noise from air vent before turning a/c on
Asked by SableMichael Oct 29, 2014 at 06:51 PM about the 2009 Mercury Sable Sedan FWD
Question type: Maintenance & Repair
I get a loud knocking or ticking from inside passenger side dashboard when I start the car. Noise goes away immediately when I turn the a/c on. Any repair suggestions?
3 Answers
Auto_Reserve answered 10 years ago
Most likely a blend door is getting hung up. Does the noise come back if you turn the ac back off or just when you first start you car?
SableMichael answered 10 years ago
Thanks for response! Noise is just at start up.
Auto_Reserve answered 10 years ago
Try turning the vents from defrost, to floor and back and see if the noise happens along the way. Sometimes these are easy to get to. Often it requires removal of part if not all the dash. Check your carpet on the passenger side foot well under the dash portion. Make sure it does not feel damp.