[Audifan]

Originally Posted by Mattstrete

I'm having the fix installed first thing tomorrow morning. I will keep you guys updated as to whether it is successful (it may take me a while to confirm). Thank you SO much OP.

Thanks. I finally got a Canadian dealer to acknowledge that the bulletin exists - though it's a US bulletin...they are looking at the car right now, likely I'll have to bring it back when the part(s) arrive....if the dealer deems that it qualifies...

[ft1330]

Got the parts ordered. They say it comes from Germany so it might take a while, at least a week. It's a brand new bulletin so everyone is jumping on the parts. The tech told me they just had video training on this fix. He showed me the bulletin and the pics show a very simple 2 part circular weight to clamp around the hose.

The tech was very pleased that I printed and showed him OP's post, he said it made it a hell of a lot easier for them. So THANKS OP!!!

[gomichaelkgo]

I zip tied some bolts that look about as heavy as the metal clamp to that spot on my hose. I haven't heard any rattle since I did it, but this 335 rattles a fraction that my first one did. I'll get the clamp installed at my first service, as my second 335 only has 1200 miles on it thus far.

[BMHunden]

I had the aircon pipe dampening weight and clamp installed today. The head of my dealer's workshop reported that he had then taken my car on a 20km test drive and that he had been unable to reproduce the resonance. I was unable to do so on my way home, so I am cautiously optimistic that this has fixed the problem.

Apparently, a similar problem was encountered with the e90 3 series and with one of the Mini models. Also, the weight appears to be the exact same part which is used on the Mini for the same purpose.

I would have thought that it is a simple job to attach the dampening weight to the aircon pipe but the entire aircon system apparently has to be drained before the pipe is removed in order to enable the weight to be attached.

As someone on this thread noted, the pipe already has a weight installed higher up, i.e. closer to the bulkhead. I was told that part of the fix also entails moving the existing weight further "down" the pipe, i.e. towards the front of the car by 25mm, or ensuring that it is correctly placed at this position.

I was quite surprised how big the weight actually is in person. It must be a good 4cm in diameter.

As I have said, I was not able to hear the familiar resonance / vibration at, and around, 2500 rpm on my way home from my dealer. Also, and this may have been my imagination, the engine now sounds smoother between 1500 and 2500 rpm. I had become ultra-senstive to the engine note in this rpm range!

Thank you, again, OP. I REALLY hope the noise is gone for good. After it went away temporarily after my radiator was reseated, and then came back, I was really despondent, but I reckon that this is now a permanent fix.

[BavarianFanatic]

Originally Posted by Mattstrete

I had the aircon pipe dampening weight and clamp installed today. The head of my dealer's workshop reported that he had then taken my car on a 20km test drive and that he had been unable to reproduce the resonance. I was unable to do so on my way home, so I am cautiously optimistic that this has fixed the problem.

Apparently, a similar problem was encountered with the e90 3 series and with one of the Mini models. Also, the weight appears to be the exact same part which is used on the Mini for the same purpose.

I would have thought that it is a simple job to attach the dampening weight to the aircon pipe but the entire aircon system apparently has to be drained before the pipe is removed in order to enable the weight to be attached.

As someone on this thread noted, the pipe already has a weight installed higher up, i.e. closer to the bulkhead. I was told that part of the fix also entails moving the existing weight further "down" the pipe, i.e. towards the front of the car by 25mm, or ensuring that it is correctly placed at this position.

I was quite surprised how big the weight actually is in person. It must be a good 4cm in diameter.

As I have said, I was not able to hear the familiar resonance / vibration at, and around, 2500 rpm on my way home from my dealer. Also, and this may have been my imagination, the engine now sounds smoother between 1500 and 2500 rpm. I had become ultra-senstive to the engine note in this rpm range!

Thank you, again, OP. I REALLY hope the noise is gone for good. After it went away temporarily after my radiator was reseated, and then came back, I was really despondent, but I reckon that this is now a permanent fix.

They have to disconnect the line in order to install it? Why in the world don't they use a split weight for the retrofit?

[Tjcf14]

My install took 10 mins. The dampener was a grooved split weight. The hose clamp tightened the two halves around the hose. Very easy install. No changes were made to the other weight on the forward end of the hose.

Also wanted to thank all the OPs who provided detailed posts and videos of these issues over the past few months. Those were extremely helpful in solving this problem.

[Steven1077]

Does anyone know if there are fitting this at the factory on new 335i/435i?

[claykin]

Originally Posted by BavarianFanatic

They have to disconnect the line in order to install it? Why in the world don't they use a split weight for the retrofit?

The weight retrofit is 2 piece. Shouldn't be any reason to discharge system or remove pipe to install weight /clamp

[claykin]

Originally Posted by Steven1077

Does anyone know if there are fitting this at the factory on new 335i/435i?

Production beginning Nov 2013 has a new part number for low pressure A/C hose. So I'd say this is addressed if your car is enroute or in production now.

[Coolhydro]

My service advisor said he is not aware of any such bulletin. Is there a number/ID associated with this service bulletin for it to show up in their records?

[Tjcf14]

Sure. The SIB number is listed on my first post and the service order. Are you in USA? OPs have said that other countries haven't received the SIB yet but many have already ordered the parts.

[ft1330]

Originally Posted by BavarianFanatic

They have to disconnect the line in order to install it? Why in the world don't they use a split weight for the retrofit?

IT IS a split weight. That's why I don't get this guy's comment. It looks like a 5 minute job.

[Steven1077]

I'm guessing he misread something

[Audifan]

Originally Posted by Coolhydro

My service advisor said he is not aware of any such bulletin. Is there a number/ID associated with this service bulletin for it to show up in their records?

Thanks to OP, SIB 64 01 14

[Coolhydro]

Thank you!

[claykin]

Originally Posted by Coolhydro

My service advisor said he is not aware of any such bulletin. Is there a number/ID associated with this service bulletin for it to show up in their records?

Ask the SA to speak with the shop foreman. The bulletin was released early last week.

[BMHunden]

Originally Posted by ft1330

IT IS a split weight. That's why I don't get this guy's comment. It looks like a 5 minute job.

"This guy" had it explained to me face to face and I was showed the weight under the bonnet.

[BMHunden]

I can confirm that the 2500rpm rattle/vibration has not reappeared after two days of driving. The engine note now sounds totally smooth between 1500 and 2500 rpm, where it previously set my teeth on edge even if I couldn't hear the actual vibration itself. Good luck to everyone else, and thank you again OP.

[ft1330]

Originally Posted by Mattstrete

"This guy" had it explained to me face to face and I was showed the weight under the bonnet.

shown

[Faszination]

Also make sure to test your cars at 5000rpm range. Mine is making the noise at 2200 and 5000. Place the car in M2 mode on the tranny, rev it up to 5000 (after the engine is warm of course) and hold the engine at 5000 or so rpms.

This is great news. Thanks to all who have worked on this.

[bananachipz]

Originally Posted by Audifan

Thanks to OP, SIB 64 01 14

Hey Audifan,

which dealer did you go to? I'm in Toronto as well.

[Audifan]

Queenway location - service only , they are affiliated with Parkview and Toronto BMW, same owners. I recommend dealing with the Queensway location in Etobicoke