Jun 10, 2015, 06:49 PM
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New DI Engines -- Excessive Carbon Buildup ??
Super Member
Joined: Oct 2012
Posts: 583
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2026 GLC300 4Matic (X254)
I'd think at this point if we were going to start seeing problems, we would by now.
I'm at 13 months and 11K miles with no issues so far. The car only gets 91 or 93 octane and averaged 24.1MPG combined over the last 10 tanks. I reset the trip computer at 1,000 miles on it and have not touched it since and it reads 23.4MPG over the last 10K miles.
In the US, the car is not known as the C250 CGI. It's just known as the C250 - providing wonderful loads of confusion for our neighbors to the north who have C250 V6es...
I'm at 13 months and 11K miles with no issues so far. The car only gets 91 or 93 octane and averaged 24.1MPG combined over the last 10 tanks. I reset the trip computer at 1,000 miles on it and have not touched it since and it reads 23.4MPG over the last 10K miles.
In the US, the car is not known as the C250 CGI. It's just known as the C250 - providing wonderful loads of confusion for our neighbors to the north who have C250 V6es...
And yes, I'm in DC/VA, I know it's called the C250. I referenced CGI precisely so the V6 C250s up north don't get nervous (thinking they have this new potential issue they've never head of)
MBWorld Fanatic!
Joined: Oct 2010
Posts: 1,128
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From: Acapulco Mexico
2010 C300 Sport
There is also the new 3.0L V6 twin turbo that will be fitted to the E400, that produces 333 HP and 369 lb-feet of torque for Europe, this may be slightly detuned for the US market due to high sulfur content gasoline. Was unable to locate this new engine model number.
It is also to be seen if the 2014 E400 Hybrid comes with this 3.0L TT engine or the 3.5L M276, as the electric motor adds 27 HP and 184 lb-feet torque at low RPMs.
It is also to be seen if the 2014 E400 Hybrid comes with this 3.0L TT engine or the 3.5L M276, as the electric motor adds 27 HP and 184 lb-feet torque at low RPMs.
Junior Member
Joined: May 2008
Posts: 54
Likes: 8
From: Austin, TX
2018 GLC 300
Porsche switched to DI motors in '09 for the 911 and I haven't seen any complaints after following the 997.2/911 forums for the past 3 to 4 years.
I see someone posted images of a Cayenne with major problems, but maybe 911's are OK due to the flat 6 design, who knows???
Just sharing my observations as another point of reference...
I see someone posted images of a Cayenne with major problems, but maybe 911's are OK due to the flat 6 design, who knows???
Just sharing my observations as another point of reference...
MBWorld Fanatic!
Joined: Nov 2001
Posts: 5,851
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From: Huntington Beach, Ca.
'17 Jaguar XF
Good informative thread. I am in the "don't buy the fact that MB has the problem solved" camp but I'm sure collectively the industry will come up with an acceptable fix/answer. When I recently asked a dealer MB mechanic about the problem with 2012 & 2013 E350s his reply was "we are running out of engine stands". First, I'm sure they don't have a lot of engine stands used or not. But at this early stage of the E350 here it doesn't look good. Last contribution: I read an article where a manufacturers Engineer (Toyota?) said the reason for the DI and port injection combination was that DI was more efficient at low RPMs and port injection more efficient (better mixing) at high RPMs. He didn't comment on cleaning the valves so I assume it was an unintended bonus. I'm guessing oil technology will be the 'simple' fix that is not so simple to find.
MBWorld Fanatic!
Joined: Jul 2007
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From: Germantown, MD/Rehoboth Beach, DE
2024 GLS450
Good informative thread. I am in the "don't buy the fact that MB has the problem solved" camp but I'm sure collectively the industry will come up with an acceptable fix/answer. When I recently asked a dealer MB mechanic about the problem with 2012 & 2013 E350s his reply was "we are running out of engine stands". First, I'm sure they don't have a lot of engine stands used or not. But at this early stage of the E350 here it doesn't look good.
If there were an issue, we would have been hearing about it by now... Where are the posts on here about these E classes in the shop with their engines out? Surely we have enough enthusiasts on here that could have/would have been experiencing this problem and would have posted about it...
MBWorld Fanatic!
Joined: Nov 2001
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From: Huntington Beach, Ca.
'17 Jaguar XF
....If there were an issue, we would have been hearing about it by now... Where are the posts on here about these E classes in the shop with their engines out? Surely we have enough enthusiasts on here that could have/would have been experiencing this problem and would have posted about it...
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
This condition for any DI manufacturer is going to be extremely fuel quality dependent. Benz certainly seems to have no problem with high quality Euro fuels. I've been keeping an eye on the situation here where we have some new Benz DI engines with growing mileage & some old CGI Benz engines and fuel that has a way to go to meet Euro 4 much less 6. Thusfar no issues but time will tell. I've boroscoped one car & it was OK at approx 60K Kms IIRC. One swallow does not make a spring however.
We must continue to keep an eye on it & see what develops & where.
We must continue to keep an eye on it & see what develops & where.
MBWorld Fanatic!
Joined: Jul 2007
Posts: 1,351
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From: Germantown, MD/Rehoboth Beach, DE
2024 GLS450
Not enough '12 & '13 E classes with sufficient mileage to have the problem? The owners with enough mileage don't notice the symptoms coming on? It only happens to people that do X? A handful at one dealer surely isn't a trend but it means the motors are prone to the problem.....no? Time will tell.
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Super Member
Joined: Oct 2012
Posts: 583
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2026 GLC300 4Matic (X254)
My MB dealer (American Service Center in Arlington VA) has a service by BG called a Fuel Induction Service. Apparently it is not just a fuel tank additive, but something hooked into the engine. I've seen some people do something similar on VW/Audi products.
Their service department sucks in terms of explaining anything over the phone (or email for that matter), so I don't know the details, but I'm guessing they are anticipating having to chemically treat some intake areas periodically. I'm fine with that if it actually works and isn't as labor intensive as the BMW/MINI walnut shell method.
Their service department sucks in terms of explaining anything over the phone (or email for that matter), so I don't know the details, but I'm guessing they are anticipating having to chemically treat some intake areas periodically. I'm fine with that if it actually works and isn't as labor intensive as the BMW/MINI walnut shell method.
MBWorld Fanatic!
Joined: Nov 2001
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From: Huntington Beach, Ca.
'17 Jaguar XF
C's, E's, SLK's, GLK's, ML's all are using forms of these engines for 2012 and 2013 (both the M271 and M276) so there is a fairly large sample size. I'm on the low end of the mileage spectrum having had my car 15 months and 12K miles - there are some out there in the 30s and 40s though.
MBWorld Fanatic!
Joined: Jul 2007
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From: Germantown, MD/Rehoboth Beach, DE
2024 GLS450
I just talked to my service writer - I'm having an errant random misfire issue that everyone is scratching their head at. As part of troubleshooting, they ended up boroscoping my cylinders and pulling the intake apart to look at it.
At 19K miles, everything within the intake (including the back of the valves) is spotless.
At 19K miles, everything within the intake (including the back of the valves) is spotless.
Super Member
Joined: Jun 2009
Posts: 584
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From: Los Angeles
2012 C250 Sport
I just talked to my service writer - I'm having an errant random misfire issue that everyone is scratching their head at. As part of troubleshooting, they ended up boroscoping my cylinders and pulling the intake apart to look at it.
At 19K miles, everything within the intake (including the back of the valves) is spotless.
At 19K miles, everything within the intake (including the back of the valves) is spotless.
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
I just talked to my service writer - I'm having an errant random misfire issue that everyone is scratching their head at. As part of troubleshooting, they ended up boroscoping my cylinders and pulling the intake apart to look at it.
At 19K miles, everything within the intake (including the back of the valves) is spotless.
At 19K miles, everything within the intake (including the back of the valves) is spotless.
Junior Member
Joined: Dec 2009
Posts: 72
Likes: 0
2010 GLK 350 4MATIC
Does anyone know if recent models of C-Class or GLA have any engineering solution to this carbon build-up problem? The GLA marketing materials say "3rd generation direct injection" and I have heard other brands have added extra injectors to ensure the intake valves get a regular wash/cleaning.
Do the latest engines from Mercedes do this as well?
I am considering a 2016 GLA and my 335i recently had this problem. Hoping to avoid it on my next vehicle. The GLA forums seem kind of quiet and I know that GLA shares engine platform with C-Class, so posting here to see if anyone has an idea?
Do the latest engines from Mercedes do this as well?
I am considering a 2016 GLA and my 335i recently had this problem. Hoping to avoid it on my next vehicle. The GLA forums seem kind of quiet and I know that GLA shares engine platform with C-Class, so posting here to see if anyone has an idea?
Senior Member
Joined: Feb 2010
Posts: 473
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From: SF bay area
C300 sport
Does anyone know if recent models of C-Class or GLA have any engineering solution to this carbon build-up problem? The GLA marketing materials say "3rd generation direct injection" and I have heard other brands have added extra injectors to ensure the intake valves get a regular wash/cleaning.
Do the latest engines from Mercedes do this as well?
I am considering a 2016 GLA and my 335i recently had this problem. Hoping to avoid it on my next vehicle. The GLA forums seem kind of quiet and I know that GLA shares engine platform with C-Class, so posting here to see if anyone has an idea?
Do the latest engines from Mercedes do this as well?
I am considering a 2016 GLA and my 335i recently had this problem. Hoping to avoid it on my next vehicle. The GLA forums seem kind of quiet and I know that GLA shares engine platform with C-Class, so posting here to see if anyone has an idea?
Any other solutions? Walnut blasting.
For my brother's 335i with the N54 engine, we did it around 55k miles based off of what the other forum members were experiencing in terms of carbon build up. It cost $450, and the car felt like new immediately after. BMW or other indy shops charge upwards $800, but if you look around, you may find a good indy shop that will do it for a reasonable price.
As for the M270 or M276, I wouldn't know, but it wouldn't hurt to open the intake valves and check certain mileage intervals. Maybe you could spend a a little extra every few years to keep your car running well if the "3rd generation direct injection" doesn't keep it as clean as you'd like.
***EDIT: This is assuming that the intake valves are easily accessible.
Last edited by Rodpwnz; Aug 28, 2015 at 03:19 PM.
MBWorld Fanatic!
Joined: Jul 2007
Posts: 1,351
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From: Germantown, MD/Rehoboth Beach, DE
2024 GLS450
40K and not a single bit of change in drivability or fuel economy here. I haven't had reason to have it scoped again, but I have no reason to believe there's any buildup. My car is now a Fri-Sun driver, and the truck is my everyday driver, so the miles are not piling on any more, though.
The GLA doesn't share the same engines with the W204 C Class though. The CLA or W205 forums would be a better source of info for the 2.0L.
The GLA doesn't share the same engines with the W204 C Class though. The CLA or W205 forums would be a better source of info for the 2.0L.
Newbie
Joined: Sep 2016
Posts: 4
Likes: 0
2013 Benz GLK 350
Hi All,
I am new to this forum. We are planning to get a used 2013 Benz GLK with the M276 DI Engine. I have learned about the carbon buildup issue with DI engines but have not been able to find anything related to this particular engine. For those of you who have this engine, have you experienced any carbon buildup by now? This engine has been in production for quite a few years now and I'm assuming that by now there should be enough sample size and mileage in relation to this issue. We really like the interior upgrades of the 2013 GLK compared to the 2012. However, the DI engine is a concern to us, and if the carbon buildup is an issue with this M276 engine, we are going to look into the 2012s withe M272 engine. Thank you!!!
I am new to this forum. We are planning to get a used 2013 Benz GLK with the M276 DI Engine. I have learned about the carbon buildup issue with DI engines but have not been able to find anything related to this particular engine. For those of you who have this engine, have you experienced any carbon buildup by now? This engine has been in production for quite a few years now and I'm assuming that by now there should be enough sample size and mileage in relation to this issue. We really like the interior upgrades of the 2013 GLK compared to the 2012. However, the DI engine is a concern to us, and if the carbon buildup is an issue with this M276 engine, we are going to look into the 2012s withe M272 engine. Thank you!!!
Newbie
Joined: Apr 2014
Posts: 4
Likes: 0
2006 SLK55 AMG
Just read whole thread, probably missed the answer ...
I realize I'm late to this party, but would love it if I could tap into this thread topic for a second or two?
I drive a MB 2006 SLK55 AMG with the normally aspirated 5439cc (M113)V8 engine. I now have 124,000kms or 77,000miles. I use Mobil 1 0W-40 oil and 91 Octane Shell gasoline (can't get 93 here). Engine seems to perform fine and I'd like to keep it that way.
So, after hours of reading and absorbing and pondering I'm left wondering why water injection kits never came up? Failing head gaskets result in completely cleaned combustion chambers, carbon and all. Could not water injection (steam cleaning, for our purposes) also clean the intake valves? Turbocharged engines should see other benefits as well.
Any takers?
tn
I drive a MB 2006 SLK55 AMG with the normally aspirated 5439cc (M113)V8 engine. I now have 124,000kms or 77,000miles. I use Mobil 1 0W-40 oil and 91 Octane Shell gasoline (can't get 93 here). Engine seems to perform fine and I'd like to keep it that way.
So, after hours of reading and absorbing and pondering I'm left wondering why water injection kits never came up? Failing head gaskets result in completely cleaned combustion chambers, carbon and all. Could not water injection (steam cleaning, for our purposes) also clean the intake valves? Turbocharged engines should see other benefits as well.
Any takers?
tn
MBWorld Fanatic!
Joined: Nov 2001
Posts: 5,851
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From: Huntington Beach, Ca.
'17 Jaguar XF
OK, I'll bite. Water injection causes a whole different set of problems related to corrosion. As well, the purpose of water injection is to cool the charge and it's not 'steam' as it passes the intake valves. Replacing gas with water also reduces the power. There's many reasons why water injection isn't used anymore. Some DI engines (without standard port injectors added) that don't suffer from the buildup and whatever they are doing is what should be done.
MBWorld Fanatic!
Joined: Mar 2006
Posts: 1,375
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From: Hong Kong
2010 C200 CGI
OK, I'll bite. Water injection causes a whole different set of problems related to corrosion. As well, the purpose of water injection is to cool the charge and it's not 'steam' as it passes the intake valves. Replacing gas with water also reduces the power. There's many reasons why water injection isn't used anymore. Some DI engines (without standard port injectors added) that don't suffer from the buildup and whatever they are doing is what should be done.
MBWorld Fanatic!
Joined: Nov 2001
Posts: 5,851
Likes: 196
From: Huntington Beach, Ca.
'17 Jaguar XF
