Exhaust Rattle

[Hymiet]

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The M3 I drove the other day had an exhaust rattle. They told me that was normal?

Sounds amazing but I can't imagine the rattle is normal...

[BhamDavid]

I can't imagine that you would even begin to believe that that was true.

[Hymiet]

Originally Posted by BhamDavid

I can't imagine that you would even begin to believe that that was true.

I didn't, just wondered if it's common. Anyone else had this issue?

[Ghetto2315]

Was it at cold start-up? Both my M3 and M4 that I had before I sold them had a very bad rattle at cold start-up. Sounded like a baffle was loose causing a massive high pitch rattle.

[Hymiet]

Originally Posted by Ghetto2315

Was it at cold start-up? Both my M3 and M4 that I had before I sold them had a very bad rattle at cold start-up. Sounded like a baffle was loose causing a massive high pitch rattle.

No.. It was warmed up. We had just taken it on a 30 minute test drive. I'm sure it was just lose or something.

[rz3]

I read somewhere that it's normal until the car warms up. The car I test drove had it. Not sure what others who have taken delivery have experienced.

[tdizzle]

Watch the fast lane car or whatever that youtube reviewer is called, their latest video (and it's posted in a thread on this forum) had it when they were showing how the exhaust sounds when revved.

I'm thinking it's normal.

[IMrMark]

There is a "rattle" during the warm up, but it goes away pretty quickly. At least that was my experience.

[sebasf80]

Got my car last friday and he's doing the same thing for 30 sec and the noise goes away

[bmwm4f82]

Originally Posted by sebasf80

Got my car last friday and he's doing the same thing for 30 sec and the noise goes away

I have the same rattle. Passenger react to it. Car built june 24.

[Suave]

Yes this is normal and actually cited in the owners Manual. The rattle is the result of required emissions control systems required in this car due to tighter regulations standards but is supposed to go away in less than a minute.

[bmwm4f82]

Originally Posted by Suave

Yes this is normal and actually cited in the owners Manual. The rattle is the result of required emissions control systems required in this car due to tighter regulations standards but is supposed to go away in less than a minute.

In what part of the manual is that written? I read it quite crefuly but do not seem to remenber this part. Thanks for helping.

In another thread an owner is getting brand new exhaust on warranty.

[smedin]

This all depends on one's definition of "rattle." I really doubt that what your hearing is a loose metal piece of any kind. Just a temporary blatty exhaust sound as it heats up the cats by running super-rich upon cold start-up.

[h4nh]

I drove an M4 with 200 miles on the clock and it didn't have the exhaust rattle. I drove an M3 with 50 miles on the clock and it had a rattle upon cold start. Maybe the exhaust needs to be broken in?

[dr2ray]

Mine rattles initially upon startup but settles down by the time I pull out of my garage.

[BUCKY44]

I have the same issue seems to be the exhaust valve flaps during warm up less than a minute it goes away.

[CatchM3]

I'm actually at the Braman BMW in West Palm Beach now and having this issue looked into. I too had a high pitched rattling sound at start up. It lingers for awhile then goes away.

It sounds like something is loose. It sounds concerning.

[CatchM3]

UPDATE:

Braman BMW of Palm Beach stated that some 'rattle' is normal however they did tighten up some 'valve' and said the rattle shouldn't be as bad. If it rattle returns, they will replace the exhaust.

[bmwm4f82]

Originally Posted by CatchM3

UPDATE:

Braman BMW of Palm Beach stated that some 'rattle' is normal however they did tighten up some 'valve' and said the rattle shouldn't be as bad. If it rattle returns, they will replace the exhaust.

Please let us know your results!

[BlackCobra08]

Mine also has the coffee grinder sounds, only on cold start-up and goes away in about 30 seconds I'd say.

[Mr T]

Part of the warm up process. On my car lasts around 30 seconds then goes away......it appears louder if the car has been left to stand for a week in cool weather....

[F82FTW]

Cold start rattles are very common on new BMW's; you could go start 15 different models at your dealer and I promise you all of them will rattle briefly until they come off the high idle, maybe a little longer even.