Carbon Build up on intake valve on CGI
Thread Starter
Newbie
Joined: Feb 2018
Posts: 3
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E Class
Carbon Build up on intake valve on CGI
I have been reading up and down and researching widely regarding the possibility of carbon build-up on the intake valve on the M271 EVO (Turbo) engine used on the E250 CGI.
There was a thread a few years ago on this and it somehow has died down. There was some talk of M-B timing/design which somehow "prevented" this from occurring - at least not to the degree of "other" GDI engine but nothing really convincing. The YouTube channel Different Car Review which I like (and is the only car review channel that specifically mentions problem of carbon build ups in their reviews of used cars), did not mention this as a problem (I also asked the channel directly regarding this).
However, in term of the engine schematics, I really can't see what would prevent carbon build up from happening although the lack of any thread of this here is reassuring.
M-B made this ECU of the M271 EVO work in homogeneous injection mode in my country (Malaysia) rather than the stratified direct injection mode in Europe due to prevailing fuel types. I wonder if this makes any difference.
So the key question: Is carbon build-up on the intake valve an issue with the M271 EVO?
There was a thread a few years ago on this and it somehow has died down. There was some talk of M-B timing/design which somehow "prevented" this from occurring - at least not to the degree of "other" GDI engine but nothing really convincing. The YouTube channel Different Car Review which I like (and is the only car review channel that specifically mentions problem of carbon build ups in their reviews of used cars), did not mention this as a problem (I also asked the channel directly regarding this).
However, in term of the engine schematics, I really can't see what would prevent carbon build up from happening although the lack of any thread of this here is reassuring.
M-B made this ECU of the M271 EVO work in homogeneous injection mode in my country (Malaysia) rather than the stratified direct injection mode in Europe due to prevailing fuel types. I wonder if this makes any difference.
So the key question: Is carbon build-up on the intake valve an issue with the M271 EVO?
Member
Joined: Sep 2016
Posts: 154
Likes: 14
From: Stockton CA
92 W124 500E, 93 W201 190E, 11 C207 E350, 05 W211 E55
That carbon buildup on intake valve backs and ports that everyone talks about is directly caused by EGR. Modern Mercedes from about 2010 onward M272 M273 had fully adjustable/variable cam timing on BOTH intake and exhaust, because of this Mercedes did not have EGR pumping that garbage back into the motor (freakin brilliant) I'm unsure if 4cyl motors used same system as V6 and V8 cars.
Newbie
Joined: Nov 2011
Posts: 5
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W212 E350CDI, E200CDI, W201 190D
I just pulled the head on a 2010 E200 CGI 110 000km and i can confirm there where a lot of carbon buildup on the intake valves. There is no EGR on the engine so it must be the crank ventilation fumes and possibly turbo oil. At least i will vent the engine fumes other ways than back to the inlet.
Regards
Oddemann
Regards
Oddemann
