Exhaust flap - can you hear it?

[supraking]

Does anyone else hear their exhaust flap opening and closing while they drive with their windows open? It occurs when the throttle goes down past a certain point and is purely for noise-reduction at lower RPMs (I've read)... is there any way to keep it open all the time?

[MadMan77]

I only hear it in the morning when it opens after idling in my garage for a couple minutes.

As far as keeping it open search the DIY section for the exhaust flapper mod. There is a couple ways to do it so just look at the entire thread and decide which way you want to do it.

Edit: Here is the post: http://www.1addicts.com/forums/showthread.php?t=213042

[BrokenVert]

I hear it in the morning on a cold start.

[supraking]

So weird. I'm taking my car back to BMW and telling them to see why it's so loud. I didn't hear it the first few days but now I hear it every time it opens and closes. I'm probably going to mod it, but will just need to remember to remove the mod when I take the car back every onc ein a while.

On the 128i, I don't think that the change in backpressure will have any effect, I don't have any turbos to spool, I just want a deeper sound at low RPMs

[oneintheory]

Originally Posted by supraking

So weird. I'm taking my car back to BMW and telling them to see why it's so loud. I didn't hear it the first few days but now I hear it every time it opens and closes. I'm probably going to mod it, but will just need to remember to remove the mod when I take the car back every onc ein a while.

On the 128i, I don't think that the change in backpressure will have any effect, I don't have any turbos to spool, I just want a deeper sound at low RPMs

You don't even have to revert it back to stock when you go in...unless they look for it, they probably won't notice it, and it throws no codes.

[supraking]

Originally Posted by Phiberglass

I ziptied the vacuum hose off and took it off a few months ago and my flap hasn't opened and closed since, it's always been in the open position.

Lol... that's one of those things that I feel would let them know something's up. But as was said, they probably wouldn't ever find it, and if I reconnect it and it doesn't work, they can't really prove I disconnected it at any point.

[mr_z4mc1m_oz]

I did this mod on Friday as shown here

http://www.tyresmoke.net/forum/bmw-t...ncer-flap.html

Havent heard a single sound since. I had the car for 2 whole weeks before i noticed the sound the flapper made when opening and closing, I was shocked that BMW could make a car which made noises like that.

Anyways all fixed up and happy with the outcome ;-)

[supraking]

I'm taking it back to see if THEY will modify it to stay open, if they won't, I'm going to mod it myself. I shouldn't be able to hear it regardless so they should have some solution to the problem.

[sturgis]

The butterfly valve closes to increase backpressure, you'll usually hear it at startup, It's designed to help the engine reach operating temperature more quickly

[Evice]

Somehow I like hearing it, makes me feel that my bimmer is actually alive.!

[supraking]

Took it back to my dealership, they kept it a day, and they're ordering new parts (muffler, exhaust, etc.). Regardless of whether it's not hurting the car, it sounds annoying when I rev, sounds like something is broken, and they said it shouldn't be doing that.

[Evice]

Originally Posted by supraking

Took it back to my dealership, they kept it a day, and they're ordering new parts (muffler, exhaust, etc.). Regardless of whether it's not hurting the car, it sounds annoying when I rev, sounds like something is broken, and they said it shouldn't be doing that.

I just hear it in the mornings... never after that.. so yours might be a different issue?