Strange Noise in Air Conditioning

[idjiot]

I noticed that my car has a weird "flapping" noise coming out of the A/C vents when I turn them on - I believe this only happens when it is really hot - which explains why the A/C is on.

Anyhow, if I lower the speed of the fan manually - I usually just push the auto button - and then let it go for a few minutes and then push it back up, the noise usually goes away.

Has anyone experienced something similar? Is there any way for me to figure out what's causin this problem without opening up the entire thing?

It doesn't seem like a big deal but I guess it's a tad annoying.

[CJ_Boxster]

Probably a leaf getting caught in your fans, I had the same issue weekago, First i sucked up all the leafs and debris around the battery then turned the ac vents on full power and placed my shop-vac nozzle over the vents and it sucked out afew more little leafs from each vent...ever since then all i've had is one leaf shoot out, but no fan noises anymore.

[MNBoxster]

Originally Posted by idjiot

I noticed that my car has a weird "flapping" noise coming out of the A/C vents when I turn them on - I believe this only happens when it is really hot - which explains why the A/C is on.

Anyhow, if I lower the speed of the fan manually - I usually just push the auto button - and then let it go for a few minutes and then push it back up, the noise usually goes away.

Has anyone experienced something similar? Is there any way for me to figure out what's causin this problem without opening up the entire thing?

It doesn't seem like a big deal but I guess it's a tad annoying.

Hi,

I can't tell specifically, but since it's Fan speed dependent, wonder if it's not a bearing in the blower motor. When these start to go, they can often be made to quiet by doing exactly as you describe. If I'm correct, it won't be long before you won't be able to make it stop and then you're replacing the motor (or the bearing if replaceable, probably not). Hope this helps...

Happy Motoring!... Jim'99

[RandallNeighbour]

Or, it could be a piece of insulation stuck in the fan, which is typical for older boxsters. It gets dry and pulls away. The fan is located above the passenger footwell. All you have to do is pull down the cover under that area and have a look with a flashlight, removing any you find with a pair of needle nose pliers.

Someone recently wrote a thread about this (1-2 months max). You might do a search.

[idjiot]

I'm going to bring my vacuum cleaner to the garage and see what we can find. Hope this works!

Thanks for the tips!