[Nordic_Kat]

My E93 is approaching its 3rd birthday. Last year was a banner year regarding stressing the A/C with an entire summer full of +100°F days. This year summer temps are hovering more in the 95-99°F range. That being said, I've noticed a funny little popping noise as the A/C settles in (about 7-10 minutes after the car is started on a hot day).

Is this normal? A/C seems to be working fine.

I am due to take the car in for a yearly service so if this is something the dealer needs to check, now is a good time.

Input?

TIA

-Kat

 

[Fripp1964]

HAHA..I had to chuckle to myself...mine does the same thing at about the same exact spot in my commute to work every morning. It almost sounds like a ball that has dropped or rattled into place. It appears to come from behnd the dash on the passenger side behind the vents?
System works fine.

Any help from anyone...curious minds want to know.


J

 

[VirtuousWolf]

Mine makes a weird noise when lime yours, but it also happens when I turn it off. To me it sounds like something is closing

 

[LarkHouston]

It is reminding you that it is a convertible. You shouldn't be using the A/C.

 

[TJPark01]

Check the small things first.
1. Cabin Air filter
2. Vents around the outside for leaves and debris.
3. Check to see if the compressor is behaving properly and that the radiator isn't filled with grease and dirt and the fan isn't damaged.

http://www.youtube.com/watch?v=B3CH6DbpRmM&feature=player_embedded

 

[thekurgan]

Is it the plastic contracting from being cooled? Also, the flap actuators, from what I've read, are a weak plastic gear so maybe with the heat .... who knows. My cars always have some kind of clicking if the car has been in the heat, then the a/c starts to cool the plastics in the ducts to the vents.

 

[Nordic_Kat]

It is reminding you that it is a cabrio. You shouldn't be using the A/C.

FIXED! :angel: Don't you run your roadster top down and A/C blasting? That's the only way to run top down in Houston June-August.

Check the small things first.
1. Cabin Air filter
2. Vents around the outside for leaves and debris.
3. Check to see if the compressor is behaving properly and that the radiator isn't filled with grease and dirt and the fan isn't damaged.

http://www.youtube.com/watch?v=B3CH6DbpRmM&feature=player_embedded

I definiitely know it's NOT an issue with my debris baskets - those puppies get cleaned out very regularly. - ie weekly. The car cools very rapidly so I doubt that it's a compressor issue. In Cabin Air Filter??? That may be.

Is it the plastic contracting from being cooled? Also, the flap actuators, from what I've read, are a weak plastic gear so maybe with the heat .... who knows. My cars always have some kind of clicking if the car has been in the heat, then the a/c starts to cool the plastics in the ducts to the vents.

Fripp described it best. It sounds like a ping pong ball has plopped into a receptacle. Just a little "'pop" then nothing more. I've pretty much dismissed it, attributing it to expansion/contraction within the system, but as it had become more noticeable in the last few weeks and the car is going in for a visit to the dealership I thought I'd ask and see if anyone had insider knowledge/intel.

 

[DougN]

Could it be the noise from the flap opening/closing when the AC automatically switching from recirc (using only air in the cabin) to fresh (using outside air) once it gets close to the desired temp?

 

[thekurgan]

Could it be the noise from the flap opening/closing when the AC automatically switching from recirc (using only air in the cabin) to fresh (using outside air) once it gets close to the desired temp?

Yes, I've had this happen in older BMWs. The gear gets stuck and the mechanism pops or slams, eventually, the gear needs to be replaced as it's just plastic.

 

[balexj]

This used to happen frequently in my 2007 335. I am very annoyed by noises like that and truthfully the dealership was never able to change it. I coped as best I could. I believe it is the re-circulation flap that moves to distribute air. Try and see if it does it on the non-max or recirculate functions. Hope that helps Alex

 

[LarkHouston]

FIXED! :angel: Don't you run your roadster top down and A/C blasting? That's the only way to run top down in Houston June-August.

You know, actually I very seldom run the A/C with the top down. It really doesn't seem to do any good in the Z4 and it just seems wrong.

P.S.- After I posted, I had a feeling that somebody might correct the vert/cabrio reference. :rofl: