EGR system removal

Tacho D

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CLK 230K W208
While considering how essential the EGR system is with it's inherent complexity, and potential for problems, I came across a video for it's entire removal from BMW cars where there is even a kit available with blanking plates etc. Thereby increasing reliability, and removing the clutter from the engine compartment making working on the engine far easier. Can this be done on Mercedes cars, and how will this effect emissions testing during the MOT? Will it effect economy?
 

w204benz

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2012 C200CDI AMG Sport
I think there is an old thread somewhere on this forum about disabling the older EGR systems with a few basic electronic components. On newer systems, you can just have it mapped out.
But I'm not sure about actually removing the components - on mine (OM651) the EGR appears to be tightly integrated into the engine design, I wouldn't have a clue about other engines.

I did a bit of research on EGRs before deleting mine. Immediately noticeable benefits were an improved throttle response and about 10% reduction in fuel consumption (approximate, as I neglected to do a proper before/after test). In theory there should also be less soot in the exhaust - but it's hard to confirm with a DPF.

As regards emissions, EGRs are supposed to reduce NOx but from what I've read I got the impression it's not by a significant amount (unfortunately I don't have any numbers to back that up). However, it would be reasonable to assume that the reduced fuel consumption would result in lower overall emissions, which might compensate.
I can't comment on the MOT, but I've been through my country's equivalent and had no issues. Then again, I think these tests are limited to carbon based emissions - which should actually be lower without an EGR.
 
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Tacho D

Tacho D

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I find it extraordinary that after spending so much effort over the years in removing exhaust gasses from the combustion chamber as efficiently and quickly as possible, (bigger valves, more valves, polished exhaust ports, freeflow exhaust systems etc), someone has come up with the hair brain idea of putting them back in. :D
 
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ajlsl600

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clk3202001,sl6002003 with everything regrettably sold ,A class 170cdi auto. NG/TF1800 ML250
Xactly!!! And I pretty sure I lost 4mpg after adblue delete egr was supposed to be done at same time. But I am not certain of that. I guess if I have live data for the egr it's still running. I must look far that, adblue delete wofed OK. Tho they never told me that I needed to unplug it. Found that out when "another message" appeared.
I not a fan of the delete, however as the system is non reliable and far to much to replace, and as I strongly object to being a captive cash cow to benz dreamboat pricing I have gone down that road.
 
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