2013 e89 35i exhaust rattle problem

[henrypark]

Bought a CPO car about a month ago, but found out that the exhaust has a weird noise.
When it especially at cold start and going at 2nd and 3rd gear, it makes a plastic can noise.
My brother's 335i makes a same noise, but his car is making noise only at cold start, but mine keeps having a noise when accelerating.
I recently went to a dealership to fix this, but they keep saying everything is fine.
Any comments and solutions to this?
https://www.youtube.com/watch?v=42CoIATe8pE

 

[john-e89]

:topicclosed:

Perfect.

 

[BrianD]

Sounds good to me

 

[Maniac]

Perplexed by the answers to this post?!

The issue is the valve in the exhaust, common issue, if under warranty speak to dealer otherwise there are a few workarounds for this.

 

[john-e89]

Perplexed by the answers to this post?!

The issue is the valve in the exhaust, common issue, if under warranty speak to dealer otherwise there are a few workarounds for this.

Normal start up burble no?

 

[Maniac]

Perplexed by the answers to this post?!

The issue is the valve in the exhaust, common issue, if under warranty speak to dealer otherwise there are a few workarounds for this.

Normal start up burble no?

I can hear the tinny sound of the valve closing, I suspect that is what the OP is referring to hearing at gear changes. Mine did this.

 

[BrianD]

Perplexed by the answers to this post?!

The issue is the valve in the exhaust, common issue, if under warranty speak to dealer otherwise there are a few workarounds for this.

Normal start up burble no?

I can hear the tinny sound of the valve closing, I suspect that is what the OP is referring to hearing at gear changes. Mine did this.

Ive got crappy speakers on my laptop, hence why I didn't pick up on the tinny sound of the valve closing that you heard

 

[Filtermike]

Has the vacuum pipe been removed or come off that operates the valve?

 

[henrypark]

If the sound is only during cold start, it would be okay, but this sound goes on when driving too. I bought the car CPO but it already has many problems such as rattles jnside and outside..

 

[Rathean]

I don't think the 35i engine and set-up is the most refined beast. Noisy injectors, occasional cam value rattles, variable exhaust sounds and clunky roof mechanism but I still love it to bits, and I must have got the one without cabin rattles

 

[Maniac]

If the sound is only during cold start, it would be okay, but this sound goes on when driving too. I bought the car CPO but it already has many problems such as rattles jnside and outside..

Cabin rattles are inevitable on a car with so many parts and hard suspension.

Good news is they're mostly fixable. The rattle exhaust should be sorted by replacing it under warranty. If not, you can place a small Spring around the flap mechanism to keep it from rattling too much.

Most annoying noise on mine is wastegate rattle when cold but then a lot of cars do this.

 

[john-e89]

Sorry op it sounded normal to me, but then I hav'nt heard the rattle carry on whilst driving. Goes to show the more reply's the better as you've more chance of someone who has experience with the problem picking something up like Maniac has.

 

[stuartinzg]

The best thing you can do is get under the car by the exhaust and disconnect the vacuum valve, takes 2 seconds, because that is a horrid rattle and I had it too. Then use tape to cover up the pipe and vac pump.

This is how mine sounds now I disconnected it (sounded like yours before). There is no solution other than replacing the exhaust and even then it won't last long. It is designed to keep the exhaust quiet until you put your foot down, but it's crap. It should have been set on a button (some aftermarket exhausts have these), then you can choose between loud/quiet.

https://www.youtube.com/watch?v=WVPfg_IcRus

And another

https://www.youtube.com/watch?v=8CTMak6Pwcs

No "click/rattle" anymore.

 

[Maniac]

Only issue there is that at high speed it also closes to valve to reduce drone. Disabling it increases drone. I've tried it. I fixed mine with a spring as its not the actuator but the spindle that starts to rattle after time.

It also is electrically controlled by an actuator in the boot so it's theoretically possible to have it wired up to a button.

 

[stuartinzg]

Only issue there is that at high speed it also closes to valve to reduce drone. Disabling it increases drone. I've tried it. I fixed mine with a spring as its not the actuator but the spindle that starts to rattle after time.

It also is electrically controlled by an actuator in the boot so it's theoretically possible to have it wired up to a button.

Don't notice the drone at all, that's what the car is all about

 

[TitanTim]

If under warranty then push the dealer to get the exhaust replaced as its called fobbing off. I don't see the point in disconnecting the flap to try and cure a common fault.

Tim.

 

[stuartinzg]

If under warranty then push the dealer to get the exhaust replaced as its called fobbing off. I don't see the point in disconnecting the flap to try and cure a common fault.

Tim.

Tim, the "on/off" nature of the valve is crap anyway, even when it works properly. At part throttle it's quiet, then all of a sudden loud, then quiet. Naff really.

 

[TitanTim]

If under warranty then push the dealer to get the exhaust replaced as its called fobbing off. I don't see the point in disconnecting the flap to try and cure a common fault.

Tim.

Tim, the "on/off" nature of the valve is crap anyway, even when it works properly. At part throttle it's quiet, then all of a sudden loud, then quiet. Naff really.

I'm unsure what it does on my M135i, I can hear it open after 20 seconds or so from cold start and stays quiet after that, I'm guessing its function is to ensure the exhaust gasses warm the cat quicker. Thankfully mine is nice and quiet but I think I would still push BMW to replace the exhaust if became noisy, something shiny for nothing

Tim.

 

[Maniac]

The flap is simply for noise emissions control and comfort.