"Clunk" right after starting engine

[JJM335]

I could not get a decent recording of the noise, so I will attempt to describe it.

It only happens after the car has sat for a few days and only on the initial startup. It is just one loud mechanical "clunk" right after the engine turns over. I am wondering if it could be the starter motor sticking. Has anyone else experienced this?

[nusevad]

im just guessing but could it be a throttle actuator starting to go bad? I had a weird clunk or grind noise before my throttle actuator died, had it replaced and the sound was gone.

[Race_Doc11]

I have the same noise the dealer changed the vanos tensioners right before my warranty expired and this didn't fix the issue. I still have the noise only on the first start after the car sits for a while regardless if it is cold or not. I recall hearing this noise from the early days when I got the car in 2008. I noticed if I tap the brakes few times and press them for 30 seconds before starting the car I don't get the noise!!!!. I'm curious if someone found a fix for this. My car has 33k miles
Here is a thread on the same issue.
http://www.m3post.com/forums/showthread.php?t=412843

[Fizik]

Originally Posted by JJM335

I could not get a decent recording of the noise, so I will attempt to describe it.

It only happens after the car has sat for a few days and only on the initial startup. It is just one loud mechanical "clunk" right after the engine turns over. I am wondering if it could be the starter motor sticking. Has anyone else experienced this?

Mine does this too, hopefully someone has an idea as to what it is.

[s85e90]

Normal. Many of the m cars I have been in do this including two of my own. It seems to be oil draining back from sitting. I wouldn't worry. There's a few threads about this as well

[scrammer]

From a previous post!

Normal.
Catalytic Converter Cold Start Heat Cycle. Warms the Cats quickly, reduces emissions ...

[///M Power-Belgium]

Originally Posted by JJM335

I could not get a decent recording of the noise, so I will attempt to describe it.

It only happens after the car has sat for a few days and only on the initial startup. It is just one loud mechanical "clunk" right after the engine turns over. I am wondering if it could be the starter motor sticking. Has anyone else experienced this?

Same here when my car has sat for 4-5 days in my garage !
When i drive my car every day there is no clunk noise ,or when i take her out for a longer trip 100-150 Miles the clunk noise is gone for 2-3 weeks !
So i think our cars need to be driven often and longer trips !
Here is a video it's "not" my car ,but here the clunk noise is "very loud" !
This sound....sounds very bad,and can not be good for our engine
I have about 50 % loudness of the noise in the video !
There are a lot of people with this problem !
http://www.m3post.com/forums/showthread.php?t=448577
So in the video is the clunk noise very clear and loud........and hope that we can find a solution for this problem !

[BrewRifle]

Mine does it too from time to time after sitting awhile. From what I've read on these forums it is normal.

[Race_Doc11]

Before the dealer changed the tensioners mine was as loud as in the video. Now it is very brief and not as loud. I'm not worried much since it has been there for a long time but I would love to get to the bottom of it. From what I have been reading it is not limited to a certain year production and changing the vanos oil valves does not fix the issue.

Originally Posted by ///M Power-Belgium

Same here when my car has sat for 4-5 days in my garage !
When i drive my car every day there is no clunk noise ,or when i take her out for a longer trip 100-150 Miles the clunk noise is gone for 2-3 weeks !
So i think our cars need to be driven often and longer trips !
Here is a video it's "not" my car ,but here the clunk noise is "very loud" !
This sound....sounds very bad,and can not be good for our engine
I have about 50 % loudness of the noise in the video !
There are a lot of people with this problem !
http://www.m3post.com/forums/showthread.php?t=448577
So in the video is the clunk noise very clear and loud........and hope that we can find a solution for this problem !

[///M Power-Belgium]

Originally Posted by racedoc11

Before the dealer changed the tensioners mine was as loud as in the video. Now it is very brief and not as loud. I'm not worried much since it has been there for a long time but I would love to get to the bottom of it. From what I have been reading it is not limited to a certain year production and changing the vanos oil valves does not fix the issue.

Yes,in #6 above someone said it's the cold start cycle and so normal,i'm not agreed with this, because for the moment my cold start cycle is removed with the BPM/Tune and i have still the same clunk noise !
Now i will say it again,when our cars are driven daily than there is no clunk noise !
Also it's realy strange to hear when you tap the brakes a few times and after press them for 30 secondes you don't get the clunk noise,so i realy need to try this a few weeks and will post the result ! And asking my self now what has the brake to do with this problem ?
So now the mystery is even bigger !
When can read,write, and think about it,but what we need is a solution,because we are not alone with this problem ! And i would love to see more reactions on this forum about this problem !
My car was 2 times at my BMW/Dealer but without result !
And after 2 years there is still "no" solution for this clunk noise ?!?!

[thekurgan]

I hear two sounds, that are familiar. The clunk, if it sits more than a few weeks, I get. Also, the shitty ass plastic creaking seat control cover! lol

[JJM335]

Originally Posted by ///M Power-Belgium

Same here when my car has sat for 4-5 days in my garage !
When i drive my car every day there is no clunk noise ,or when i take her out for a longer trip 100-150 Miles the clunk noise is gone for 2-3 weeks !
So i think our cars need to be driven often and longer trips !
Here is a video it's "not" my car ,but here the clunk noise is "very loud" !
This sound....sounds very bad,and can not be good for our engine
I have about 50 % loudness of the noise in the video !
There are a lot of people with this problem !
http://www.m3post.com/forums/showthread.php?t=448577
So in the video is the clunk noise very clear and loud........and hope that we can find a solution for this problem !

YES. That is the noise, but mine is a bit less than the video as well.

Thanks for the help narrowing it down.

[Race_Doc11]

I don't understand why when I press the brakes before starting the car it doesn't do it? I even developed a habit of turning the ignition on press the brakes for a while then start the car .
The dealers here are clueless and I didn't want them to tear my engine apart not knowing the fix.
I'm not convinced it is normal.

Originally Posted by ///M Power-Belgium

Yes,in #6 above someone said it's the cold start cycle and so normal,i'm not agreed with this, because for the moment my cold start cycle is removed with the BPM/Tune and i have still the same clunk noise !
Now i will say it again,when our cars are driven daily than there is no clunk noise !
Also it's realy strange to hear when you tap the brakes a few times and after press them for 30 secondes you don't get the clunk noise,so i realy need to try this a few weeks and will post the result ! And asking my self now what has the brake to do with this problem ?
So now the mystery is even bigger !
When can read,write, and think about it,but what we need is a solution,because we are not alone with this problem ! And i would love to see more reactions on this forum about this problem !
My car was 2 times at my BMW/Dealer but without result !
And after 2 years there is still "no" solution for this clunk noise ?!?!

[FormulaMMM]

Originally Posted by racedoc11

I don't understand why when I press the brakes before starting the car it doesn't do it? I even developed a habit of turning the ignition on press the brakes for a while then start the car .
The dealers here are clueless and I didn't want them to tear my engine apart not knowing the fix.
I'm not convinced it is normal.

I started a thread on this (w/ vid) a couple of years ago http://www.m3post.com/forums/showthread.php?t=705895

Since then I've heard it on a dozen M3s minimum, including both of mine. My 6MT since 14k miles when I acquired (has almost 50k now), and my DCT with 25k mls. Heard many times in person, and in random cold start M3 videos on YouTube.

Malek @ MRF's explanation here http://www.m3post.com/forums/showpos...7&postcount=20

Also briefly exchanged with Mike Benvo on the issue. Through his remote tuning he's heard it on numerous occasions on M3s around the world.

So it's either a very widespread problem, or it's normal. I lean toward the latter.

[banditM3]

I've had that noise as well on my M3, as a matter of fact I heard it yesterday. Here's what I think. I had this noise as well in the last three Acuras (TL, TL-S, TSX V6) that I've had. When I took the first one to the dealer to ask about it I was told that it was normal if the car hadn't been driven for a few days. He explained that is was the anti-lock brake system pulsing the brakes on start up to make sure the pads are seated correctly and check for the proper funtioning of the braking system. The reason I heard it yesterday is because I haven't driven my car for a few days.

To me its completely normal and I don't think twice about it and its nothing to worry about.

[///M Power-Belgium]

Originally Posted by FormulaMMM

I started a thread on this (w/ vid) a couple of years ago http://www.m3post.com/forums/showthread.php?t=705895

Since then I've heard it on a dozen M3s minimum, including both of mine. My 6MT since 14k miles when I acquired (has almost 50k now), and my DCT with 25k mls. Heard many times in person, and in random cold start M3 videos on YouTube.

Malek @ MRF's explanation here http://www.m3post.com/forums/showpos...7&postcount=20

Also briefly exchanged with Mike Benvo on the issue. Through his remote tuning he's heard it on numerous occasions on M3s around the world.

So it's either a very widespread problem, or it's normal. I lean toward the latter.

Yes saw your thread too , about Maleks explanation i'm not sure ,but i would love if it's true ! Let's hope....but with hope only our problem is not solved !
About Mike yes i know,he had the clunk noise too but now with his new engine i don't know.
Anyway i need to call him soon to turn my cold start cycle back on,and i will ask him if he has the clunk noise also with the new engine !
Damn we all need a solution,each time that i hear it,i think....this can not be healty for this engine !
Note ....one time i let my wife start the car with the hood open,and at the same time i held my hand on the engine,and i realy could feel the vibration of the clunk noise through my hand !
Conclusion for me personal....
"No" this can "not" be good for our engines !

[JJM335]

I tried holding the brake pedal down as some suggested to no avail. I actually discovered that I do this everytime I start the car anyway...probably because my DD is an auto.

I am leaning toward the starter motor more now that I have read Malek's thread. Chime in if anyone has has this actually diagnosed by a dealer.

Thanks.

[///M Power-Belgium]

Originally Posted by JJM335

I tried holding the brake pedal down as some suggested to no avail. I actually discovered that I do this everytime I start the car anyway...probably because my DD is an auto.

I am leaning toward the starter motor more now that I have read Malek's thread. Chime in if anyone has has this actually diagnosed by a dealer.

Thanks.

+ 1 !
This thread has"710" vieuws now!But sadly without any solution !
Only thing we can do is hope and wait for someone with a real solution for this clunk noise ! --->

[Race_Doc11]

Can someone who still has warranty go to the dealer and tell them to open a case with BMW?

Originally Posted by ///M Power-Belgium

+ 1 !
This thread has"710" vieuws now!But sadly without any solution !
Only thing we can do is hope and wait for someone with a real solution for this clunk noise ! --->

[///M Power-Belgium]

Originally Posted by racedoc11

Can someone who still has warranty go to the dealer and tell them to open a case with BMW?

100 % agreed !And there are a lot of ///M3 owners with the clunk noise !
Prove is that Mike (Mike-Benvo) hears it all the time and all over the world when he is tuning the ///M3's on Skype and that he has done with my car too !
Strange thing is that some are saying it's normal even with warranty,because BMW says it's normal !
But for me personal it was "never" normal ! Such a loud and weird metallic sounding clunk noise !

[soniczoom5]

yeah - i would not classify that noise as "normal"...........

[///M Power-Belgium]

Originally Posted by racedoc11

I have the same noise the dealer changed the vanos tensioners right before my warranty expired and this didn't fix the issue. I still have the noise only on the first start after the car sits for a while regardless if it is cold or not. I recall hearing this noise from the early days when I got the car in 2008. I noticed if I tap the brakes few times and press them for 30 seconds before starting the car I don't get the noise!!!!. I'm curious if someone found a fix for this. My car has 33k miles
Here is a thread on the same issue.
http://www.m3post.com/forums/showthread.php?t=412843

You are right !
I've tried like you said above to tap the brake several times and about 30 sec .
Now the mystery is even bigger ! Because i tried this today and i did not driven the car for 8 days....tap brake 5-6 X times....30 sec ....no clunck noise ?!?!
Damn ! What the "F" has the brake to do with the clunk noise ???
And the mystery continues......................................... .............