C320 knock knock/Nop Nop Nop noise
Thread Starter
Junior Member
Joined: Sep 2010
Posts: 38
Likes: 0
From: Southern Finland
C320 W201 W202
It is not engine mounts.
Telephone recording I can not transfer recordings to my computer, I have tried. Sorry
The symptoms are exactly the same as the flex plate
But why voting should not be a cold engine. Require at least 40 degrees. That heat is guestion now.
My theory: if the lesion is small or incipient, the sound should not be a cold engine,
Is that possible: heats up the metal bow and stretch and give voice to. Is this a correct theory of heat
If that heat thing is possible, the bug MUST be a flex plate onestly.
Telephone recording I can not transfer recordings to my computer, I have tried. Sorry
The symptoms are exactly the same as the flex plate
But why voting should not be a cold engine. Require at least 40 degrees. That heat is guestion now.
My theory: if the lesion is small or incipient, the sound should not be a cold engine,
Is that possible: heats up the metal bow and stretch and give voice to. Is this a correct theory of heat
If that heat thing is possible, the bug MUST be a flex plate onestly.
Last edited by C320 Make; Sep 14, 2010 at 10:34 AM.
Super Member
Joined: Jul 2010
Posts: 605
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From: Cali
2006 C230 Sedan
Hmmz.. i wonder if this is the same problem I am having. I have this nop nop nop noise. Perhaps he can check out my tread and see if that is the sound. I had posted my noise.
https://mbworld.org/forums/c-class-w...esevior-2.html
https://mbworld.org/forums/c-class-w...esevior-2.html
Last edited by 04mbc230; Sep 22, 2010 at 02:19 PM.
Super Moderator
Joined: Jun 2008
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
I have been PMing with C320 Make. We seem to have narrowed it down to a small-end bearing or piston slap - I think a damaged piston - thrust side skirt.
Super Member
Joined: Jul 2010
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From: Cali
2006 C230 Sedan
Super Moderator
Joined: Jun 2008
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Yes - it's going into the main Benz WS in Helsinki. I've told them to unload the cylinders one by one on that bank by cutting spark & seeing if the noise reduces. I'm hoping the block is OK or it's going to be very expensive.
Super Member
Joined: Jul 2010
Posts: 605
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From: Cali
2006 C230 Sedan
Well, there is just one problem to this equation. The noise sounds like it's external and not inside the enginee. I mean, if it is the piston or something inside, the noise would be muffled. But it's clear sound that is something outside.
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
C320's car is definitely looking like internal. Aluminium blocks transmit noise badly whereas cast iron blocks don't.
Super Moderator
Joined: Jun 2008
Posts: 19,942
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
https://mbworld.org/forums/c-class-w...fect-what.html
Just to close out this thread.
It was multiple small end bearing failure. The engine is being rebuilt at present. From the failure mode the best guess at cause is oil starvation at some time in the vehicles partially unknown life. The horse has bolted. We will never know how or why. Most unusual!
Apart from full bearing, rings, chains, tensioners etc replacement while apart we are fitting a new oil pump & ensuring no pickup screen blockage etc.
This is costing! Thank heaven pistons & bores are OK
Just to close out this thread.
It was multiple small end bearing failure. The engine is being rebuilt at present. From the failure mode the best guess at cause is oil starvation at some time in the vehicles partially unknown life. The horse has bolted. We will never know how or why. Most unusual!
Apart from full bearing, rings, chains, tensioners etc replacement while apart we are fitting a new oil pump & ensuring no pickup screen blockage etc.
This is costing! Thank heaven pistons & bores are OK
Last edited by Glyn M Ruck; Oct 5, 2010 at 12:05 PM.
Newbie
Joined: Jan 2015
Posts: 4
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w203 c320 4matic '04
Did your auto sound something like this? http://youtu.be/jt3ZmbjTp7w
2003.5 w203 c320 4matic
The sound is at the bottom, rear of the engine. (Towards driver, not headlights) Around transmission.
Any advice or knowledge is greatly appreciated.
2003.5 w203 c320 4matic
The sound is at the bottom, rear of the engine. (Towards driver, not headlights) Around transmission.
Any advice or knowledge is greatly appreciated.
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C320
Check your oil pressure.
Last edited by tjts1; Jul 18, 2018 at 10:52 AM.
