Buick Repair Questions? Ask a Mechanic for Answers ASAP
Hello, it is hard to say without having the vehicle in front of me but I have seen this on many different GM vehicles. The issue is usually a blend door actuator for the heat/AC blower on the passenger side. It is pretty tricky to replace but I would suggest this to your shop and have them check it out. The actuator is behind the top area of the glove box. Basically it has gears and they get stripped and that causes the buzzing noise, it will continue happening because the actuator continues trying to move until it reaches its limit. Hopefully this helps you, best of luck.
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