Assimilator1 wrote The other day when I started my engine after being laid up a week, as well as the 'normal' rattle on start up, it was then followed by a heavy clunk which I actually felt!

(shock through the car & it felt like the car jolted slightly too!). Now this has happened once before, but it was so long ago I forgot about it.
Has anyone else had this clunk & got it fixed?
That clunk is very worrying!
DrFerry wrote Yes, the start up clunk have been reported on various dedicated threads over the years. Welcome to the clunk...
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https://www.m3post.com/forums/showthread.php?t=996069
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https://www.m3post.com/forums/showthread.php?t=1292008
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https://www.m3post.com/forums/showthread.php?t=987126
Everything from the A/C compressor clutch, the alternator, the dual mass flywheel and the air pump have been researched IIRC. Let us know what you find out. PS: It's a shame England lost to Argentina in the World Cup. Obviously I'm no fan of Argentina. The investigations into numerous FIFA Referees is ongoing, but will probably go nowhere.
My S65 has the
"COLD" start up clunk and rattle noises too (always had it) just like many S65 owners ..
As far as I know , DD drivers (daily driven cars) don't get the terrible clunk noise.
Sometimes it sounds bad , really bad . I mean like a "Kalashnikov" (no kidding)!
Back in time , a good friend of mine was in my garage and I started my car up (Cold)
He was frightened by the rattle and clunk noise and said : Man WTF was that ?!?!
In the beginning I was thinking , honestly this can't be healthy for my S65.
But so far so good...It didn't hurt my engine.
How to fix it ?
Just daily drive the car , and you won't get the S65 clunk and rattle noises anymore (!) My car is a garage queen , that's why I always got it .
If I drive my car 2-3 times/week , the clunk noise is completely gone ..
Just test it out , and you will see..
After all those years, I saw for once that the clunk noise is been fixed by replacing the S65 Vanos Gears .
It was a BMW PUMA case and it was posted on this forum , as you can see and read ...