Jun 15, 2015, 04:27 PM
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The warm start engine knock
Thread Starter
MBWorld Fanatic!
Joined: Apr 2007
Posts: 1,488
Likes: 439
From: San Diego, CA
2024 EQE 500
The warm start engine knock
So I have had my 2013 C350 for about three weeks now. The other day my buddy was walking over to the car just as I started it, after it had been sitting for about an hour, and he pointed out the knock knock knock that lasts about 2-3 seconds.
I am familiar with DI motors as my Audi had one as well. That is not the sound in question. I started searching and it seems there are quite a few people reporting perceived "engine knock" on warm starts. Funny thing is I have no noises at a cold start, only warm.
My question is, how many of you have this same issue?
I am familiar with DI motors as my Audi had one as well. That is not the sound in question. I started searching and it seems there are quite a few people reporting perceived "engine knock" on warm starts. Funny thing is I have no noises at a cold start, only warm.
My question is, how many of you have this same issue?
Junior Member
Joined: Aug 2011
Posts: 37
Likes: 1
From: Munich, Germany
2013 E350 Cabriolet
Hi,
the M272 engines had these problems with too large main bearings that took a couple seconds to build up oil pressure and in the meantime caused the knocking. Those bearings get replaced on warranty by MB.
But your '13 should have an M276 engine.
Anyway, google "C300 engine knock" and you'll find a thread in another forum with sound files included.
the M272 engines had these problems with too large main bearings that took a couple seconds to build up oil pressure and in the meantime caused the knocking. Those bearings get replaced on warranty by MB.
But your '13 should have an M276 engine.
Anyway, google "C300 engine knock" and you'll find a thread in another forum with sound files included.
Super Member
Joined: Jan 2013
Posts: 670
Likes: 7
From: Alberta
2014 E63 AMG S
I have the knock as well. brought it in for service because I was actually getting stalls on startup because of it. Apparently there is an engine software update for this specific issue on warm starts. The knocking is still there, but the technician didn't seem very concerned.
MBWorld Fanatic!
Joined: Aug 2007
Posts: 1,544
Likes: 87
From: San Jose, CA
2010 c300
I have this on my used 2010 like the car is misfiring. After about 30 seconds I hear a whining sound from the front for about 3 seconds, then the exhaust sounds normal after. I've just ignored it as others have mentioned they experience the same in another thread. Is there a long term side effect to this or it has to be fixed asap.
Super Moderator
Joined: Jun 2008
Posts: 19,942
Likes: 191
From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
The 90 degree V6 had a slight tendency to piston slap with ultra short skirt pistons until the oil film had built up. I have not listened closely to many 60 degree engines & they have some DI noise.
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Super Member
Joined: Jan 2013
Posts: 670
Likes: 7
From: Alberta
2014 E63 AMG S
Just got a call from my service department, a GLK with a M276 was just brought in with concerns about the engine knock. My SA let me know that an internal document was released on the 26th of June regarding the issue of an engine knocking sound for 2-3 seconds after the vehicle has been sitting for about an hour (Consistent with my problems, and others).
He said that the problem had to do with oil pressurizing or something of that nature, and said he had ordered parts necessary to fix the problem for the GLK. He will be in contact with me if the fix was a success, and how long it may take. I'll let you guys know, you may want to contact your SA.
He said that the problem had to do with oil pressurizing or something of that nature, and said he had ordered parts necessary to fix the problem for the GLK. He will be in contact with me if the fix was a success, and how long it may take. I'll let you guys know, you may want to contact your SA.
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Thread Starter
MBWorld Fanatic!
Joined: Apr 2007
Posts: 1,488
Likes: 439
From: San Diego, CA
2024 EQE 500
Good to hear, please reply back with the outcome.
Just got a call from my service department, a GLK with a M276 was just brought in with concerns about the engine knock. My SA let me know that an internal document was released on the 26th of June regarding the issue of an engine knocking sound for 2-3 seconds after the vehicle has been sitting for about an hour (Consistent with my problems, and others).
He said that the problem had to do with oil pressurizing or something of that nature, and said he had ordered parts necessary to fix the problem for the GLK. He will be in contact with me if the fix was a success, and how long it may take. I'll let you guys know, you may want to contact your SA.
He said that the problem had to do with oil pressurizing or something of that nature, and said he had ordered parts necessary to fix the problem for the GLK. He will be in contact with me if the fix was a success, and how long it may take. I'll let you guys know, you may want to contact your SA.
Member
Joined: Mar 2009
Posts: 167
Likes: 5
From: Florida
2023 C63s Coupe, 2020 CLA 45,2018 C63 Coupe,2016 C43,2014 CLA45,2013 C350 Coupe,
I have a 2013 c350 coupe with the same knocking issue at start up for about 2 to 3 seconds so when I took the issue to my service manager at Mercedes Benz of Cutler Bay in Miami he said that noise came from the timing tensioners so they were replaced with and updated version but that did not fix the problem so the service manager called the Mercedes tech line and was informed that they were comming out with and updated check valve (thats what they called it) i have no idea what this valve does but we will find out this Tuesday when there installing the new valve for this knock issue...
Thread Starter
MBWorld Fanatic!
Joined: Apr 2007
Posts: 1,488
Likes: 439
From: San Diego, CA
2024 EQE 500
My SA says the tech diagnosed my issue as the timing tensioners like the person above posted. They are ordered and we'll see what happens in a day or two.
Super Member
Joined: Jan 2013
Posts: 670
Likes: 7
From: Alberta
2014 E63 AMG S
You should give them a call and see if they can find any documentation on the "check valve" replacement. I PM'd VFORCE09 and he said that the check valves fixed the issue, while the timing tensioner did not.
Member
Joined: Mar 2009
Posts: 167
Likes: 5
From: Florida
2023 C63s Coupe, 2020 CLA 45,2018 C63 Coupe,2016 C43,2014 CLA45,2013 C350 Coupe,
OK here is my update:
on Friday I pickup my car and so far no start knock issues
but For some reason they changed the tensioners again but also added a new updated valve that was the main reason for the knock..problem solve for me
on Friday I pickup my car and so far no start knock issues
but For some reason they changed the tensioners again but also added a new updated valve that was the main reason for the knock..problem solve for me
Last edited by VFORCE09; Jul 24, 2013 at 12:48 PM.
Thread Starter
MBWorld Fanatic!
Joined: Apr 2007
Posts: 1,488
Likes: 439
From: San Diego, CA
2024 EQE 500
Thanks for the update. Do you happen to have the part numbers on the invoice for what was replaced?
Member
Joined: Mar 2009
Posts: 167
Likes: 5
From: Florida
2023 C63s Coupe, 2020 CLA 45,2018 C63 Coupe,2016 C43,2014 CLA45,2013 C350 Coupe,
Newbie
Joined: Jul 2013
Posts: 4
Likes: 0
C350 4Matic
Thread Starter
MBWorld Fanatic!
Joined: Apr 2007
Posts: 1,488
Likes: 439
From: San Diego, CA
2024 EQE 500
Member
Joined: Mar 2009
Posts: 167
Likes: 5
From: Florida
2023 C63s Coupe, 2020 CLA 45,2018 C63 Coupe,2016 C43,2014 CLA45,2013 C350 Coupe,
here's the part numbers on the invoice for the knock noise
1. 2760502500
1. 2760502600
16. 000000006365
1. 003989982010
6. 2761410180
2. 2780504000
015702
057807
057806
015703
LI05.10-p-056435
sorry my scanner is not working right now
1. 2760502500
1. 2760502600
16. 000000006365
1. 003989982010
6. 2761410180
2. 2780504000
015702
057807
057806
015703
LI05.10-p-056435
sorry my scanner is not working right now
Newbie
Joined: Jul 2013
Posts: 4
Likes: 0
C350 4Matic
Thanks
Member
Joined: Mar 2009
Posts: 167
Likes: 5
From: Florida
2023 C63s Coupe, 2020 CLA 45,2018 C63 Coupe,2016 C43,2014 CLA45,2013 C350 Coupe,
