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Discussion Starter · #1 ·
When my car idles there is a rattle from underneath. It sounds like maybe the exhaust is tapping something. Anyone experience a similar problem or know what could be wrong?

In addition, Ive noticed lately that my transmission makes more of a whine than it did when I first got the car. Is there a way to check the fluid in the tranny on the 5 speed getrag?

Im not sure if this is related but my clutch has always grabbed at about half way out. It grabs well and was replaced about 20k ago, but this seems weird as well?

Can anyone help me with any of these issues?
 

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Hi!!
The rattle you`re experiencing at idle is propably the gearbox, try the following: when the car idles on neutral and you hear the the rattle, engage clutch-if the rattle disappears, it`s the gearbox. quite normal, mine rattles some, has allways done so.
The whine: didn`t you put resonators to you`re exhaust last week? It could just be that you hear the whine better now that yoùr car is quieter, also becoming used to the car makes you notice new sounds. Yes, the gearbox fluid is possible to check, quite simple. This is a reasonable thing to check, and possibly change just to see if there is abnormal amount of metal shavings in the magnet(on the drain plug). Is the gearchange easy or are you experiencing problems with that? fluid leaks?
all in all, your gearbox sounds quite ok.
If there isn`t dramatic change in the area of engagement for the clutch, I wouldn`t worry. In any case these shouldn`t be related. sounds like normal M5 clutch to me.

:cheers:
Sakke
 

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i just upgraded to a 6 speed box, and that rattles particularly when warm, as soon as you engage the clutch it goes away. My 5 speed box didn't do that, but it did leak oil all over the catalyst regularly, and generate a disturbing amount of heat (enough to melt the carpet where the shift kit goes thru!) so i'd gladly exchange that for a slight rattle that these boxes are known for.

as for your clutch, think that again is just how they are - i put a rmfd one in about 3 months back, and its a bit sharp, but feels fine.
 

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Discussion Starter · #4 ·
when i first noticed the rapping, i pressed the clutch but it makes no difference. And I found out what the whining was today. When Im playing cds, somehow they pick up on the tranny sound? If my stereo is off theres pretty much no whine at all. If I have it on, as I drive through the gears and even at idle it makes it sound like it has a race car gearbox. A very noticeable whine..
 

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You are describing alternator whine. If you have not changed any audio components then you need to check your grounds. One of them may have come loose and poor grounding causes alternator whine. If you have changed components recently then you also need to check the wiring you used. Make sure all wires are "shielded" especially any RCA type interconnects.
As for your "rapping" sound, someone said you recently changed your resonator. Check to see that any heat shielding has not come loose and is banging against your exhaust system.
 

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Discussion Starter · #6 ·
WylM5 said:
You are describing alternator whine. If you have not changed any audio components then you need to check your grounds. One of them may have come loose and poor grounding causes alternator whine. If you have changed components recently then you also need to check the wiring you used. Make sure all wires are "shielded" especially any RCA type interconnects.
As for your "rapping" sound, someone said you recently changed your resonator. Check to see that any heat shielding has not come loose and is banging against your exhaust system.
the whine seems to actually come out of the speakers though..
 

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Red,

The alternator whine will come thru your speakers, especially your tweeters. The whine will correspond to your engine speed. I did a Google search and found this web site informative.

www.mmxpress.com/technical/noise.htm

There are many more sites but this one seems to give a fairly good explanation without getting into too much technical jargon.
 

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WylM5 said:
Red,

The alternator whine will come thru your speakers, especially your tweeters. The whine will correspond to your engine speed. I did a Google search and found this web site informative.

www.mmxpress.com/technical/noise.htm

There are many more sites but this one seems to give a fairly good explanation without getting into too much technical jargon.
------------

Thanks Wylm5 - I had a 30gb hard drive stereo wired in and I get the alternator whine - sounds a bit like a turbo!

I thought you could buy some fuse or something that reduces it, my local electrical and audio shop showed it to me, but reckoned it does not work that well on the e34's.
 

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Jahangeer said:
------------

Thanks Wylm5 - I had a 30gb hard drive stereo wired in and I get the alternator whine - sounds a bit like a turbo!

I thought you could buy some fuse or something that reduces it, my local electrical and audio shop showed it to me, but reckoned it does not work that well on the e34's.
30gb hard drive stereo sounds quite cool! I have a Pioneer MP3 head unit that works quite well.
As far as getting rid of the whine via a supressor I would recommend against it. A supressor works by filtering out that "whine", unfortunately it will only supress and not eliminate the problem. I would use a supressor only if I was unable to find the problem.
 

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Discussion Starter · #10 ·
wait so is what im hearing indicating my alternator is bad? Or just that my stereo is improperly hooked up? It defenitly didnt do this when I first got the car..
 

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redl1nerpm said:
wait so is what im hearing indicating my alternator is bad? Or just that my stereo is improperly hooked up? It defenitly didnt do this when I first got the car..
Have you read the links provided earlier in the thread concerning alternator whine? if not-do it. There`s propably nothing wrong with the alternator, but posible there could be a loose earth connection or something like that. I also have this whine, have always had. in my case it propably depends on the way stereo is hooked up-it`s pretty discreet though so I can`t bother to do anything with it....

cherrsagai
Sakke
 

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Red,

Yes, your alternator may be bad BUT that would be one of the last things I check. I know you want a pin point answer but the truth is that there are many, many things that can introduce noise into your audio system. If you want a simple fix I would suggest an alternator whine supressor. While I don't like them it may be good enough a fix for you and will be very straight forward and quick. You should be able to get one from any car audio shop.
One last note, since you indicate that this problem only started recently I would really suggest checking your grounds as one probably has come loose.
 

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Discussion Starter · #13 ·
WylM5 said:
Red,

Yes, your alternator may be bad BUT that would be one of the last things I check. I know you want a pin point answer but the truth is that there are many, many things that can introduce noise into your audio system. If you want a simple fix I would suggest an alternator whine supressor. While I don't like them it may be good enough a fix for you and will be very straight forward and quick. You should be able to get one from any car audio shop.
One last note, since you indicate that this problem only started recently I would really suggest checking your grounds as one probably has come loose.
I was messing the my amp (its aftermarket) recently and i think thats when it began. Theres a lot of adjustments on it so Im sure I just messed something up with that. When I get my new deck this week Ill make sure everythings good and check the amp.
 

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Thank god other people are getting some 'rattle with clutch disengaged - but disappears when engaged' type of noises.....it kind of re-assures :)

I did initially think it was a sign of impending doom......but sounds like wear in idler gear or thrust bearing?
 

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Discussion Starter · #15 ·
the whining was the alternator. What caused it was really ****ty wiring for the stereo that the previous owner obviously installed himself. I had a new stereo put in and the wires all properly done this time including the ones for the amp and subwoofer. Now it doesnt whine and the quality is much better.
 
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