Remap and EGR delete/removal/blanking

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Active Member
Aug 1, 2020
2011 C250 CDI
Morning all,

I'm.sorry if this question has been asked before but I have searched and can't find the answer.

My 2011 C250 CDI is going in for a remap on Thursday and I have opted to have the EGR disabled in the software.

My question is, will this be enough to render the EGR inoperable or like my previous cars (non mercedes) will I also need to fit a blanking plate or unplug the valve completely?

I believe my engine is the OM651.

Thanks in advance,

that will make it illegal to use on the road and also it's needed to regen the dpf, you would need to blank it off to be sure
I had the egr ‘delete’ done on my 2007 OM642 engine. The company that did mine advised the plate wasn’t needed (ask your company if you need one), and said they do not ‘delete’ it completely, but change the amount the valve opens to a tiny %. I presumed that way the car still thinks it has the valve, but the amount of gasses recirculated is minimal.
Thanks for your responses guys.
that will make it illegal to use on the road and also it's needed to regen the dpf, you would need to blank it off to be sure

Most egr , dpf / decat Police are on car forums and not reality .

I too thought the egr was a prerequisite to successful dpf regeneration but was quickly corrected by a top tuners experiences .

Blank only required for a faulty partially open egr valve.
I had it turned off in the ECU but he said a small amount of gas will get past so I fitted a blanking plate.
that will make it illegal to use on the road and also it's needed to regen the dpf, you would need to blank it off to be sure

I wouldn't advise anyone to tinker with the vehicle's emissions control systems, it is selfish and inconsiderate of others.

That said, from what I read, EGR delete isn't illegal strictly speaking. See below:

I can actually understand while people aren't happy about having black soothy fumes fed back into the intake manifold and digested by the injectors.

But I still don't recommend tempering with the EGR.... it reduced NOx emissions. Which are harmful.
I think people delete/ blank it off as it is seen to cause so many issues. (rightly or wrongly) I kind of get why people would although I havent.. & wont be.
The emissions woudnt be that much different... and nobody will die from an egr delete.. ;-)
Exactly why I did it. I work in the motor trade and have seen a lot of coked up inlet manifolds and swirl valves caused by the EGR system mixing with PCV oily vapours.
i took the egr off my old Audi 1.9tdi just to see what state it was in. I was shocked as it was totally blocked, just one big block of carbon and locked solid. Might aswell have been blanked off.
Car ran sweet and always flew through the emissions test, even the tester would comment on how low the readings were. So I question how much difference they really make.. I cleaned it out properly but noticed no difference afterwards.

Pretty sure VW have offset any dangerous emmisions from individual blanked off egr valves with their massive scandle about diesel emissions from their cheat device... I would do what ever you fell happy doing..
Nothing much is going to help a hopeless out of date design.

It reduces NOx not eliminates it at the expense of several negatives !

Diesel fuel combustion cycle does leave some incomplete burnt fuel molecules - soot.

The soot combines with recirculating crank case oil vapour to create this super gunk .

Then there's these wonderful ecu emissions updates that will see the egr opening even more thus more gunk .
Cars that drive up and down the motorway are less likely to get their intakes coked up.... The ones that drive to get a pint of milk are the ones that complain how diesel pollution devices are affecting their cars.

Simple , get a petrol car if your trips are short .

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