E320 Decat - Scarred witless

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K9 JSB

Member
Joined
Jun 7, 2014
Messages
35
Car
W211 E320 CDI Avant Garde
After hours of scouring Google for advice & information on decatting my W211 E320 CDI, I've managed to obtain pretty much nothing.. :confused:

In fact I've been left with more questions and worries than I initially started with :doh:

Okay, i'm going to quick fire my questions off and hope MBUK can be of assistance to me and anyone else looking for info :thumb::thumb:


Will I be left with an Engine Warning light on display afterwards ?

Am I going to gain an undesired or deafening sound from the exhaust ?

Is there going to be excess smoke or thicker black smoke under acceleration ?

Will MOT's become an issue ?

Does a decat open a car up to other issues ?
 
No to almost everything. You may get an unwanted drone from the exhaust when cruising on the motorway. And a very picky mot tester will notice yes.
Are you gutting the cats or removing them?
 
Thank you very much for the reply (and the peace of mind)

As of now I do not know, I just know I need it done before the remap and DPF removal from MSL. (And possibly EGR valve removal once I've gained some info, but, that's another thread for another day)


I don't even know who can carry this work out, information for decatting is such dark zone for anything over 2 litre
 
Why are you doing it? Cats are there for a reason: they significantly clean up the exhaust gases.
 
Cos on these they get blocked up, and increase fuel useage, thereby polluting more.....
 
I am very keen to unlock more of the V6's potential.

My plans, in order of plan are..

Decat
DPF
EGR valve
Remap

I understand the catalytic convertor serves a purpose, but, from what I understand it is extremely beneficial for performance and longevity of my car and engine to remove this (selfishly at the cost of the environment, which I am more than aware of) :dk:

Also the expense of replacing a cat upon any issues and the gain of MPG
 
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I rather think that if you remove the DPF the car will fail an MoT.
 
Thank you very much for the reply (and the peace of mind)

As of now I do not know, I just know I need it done before the remap and DPF removal from MSL. (And possibly EGR valve removal once I've gained some info, but, that's another thread for another day)


I don't even know who can carry this work out, information for decatting is such dark zone for anything over 2 litre

Email sent

thanks

Acid
 
EGR valve is the one thing I know ZERO about and wouldn't consider touching it until I know all the facts. All I know is its very common for tuners to have these removed.

WhiteNemesis Im just about to read your link, looks educational and interesting. Hopefully just what I need before making a decision regarding my EGR valve

Matt@RebelionIm Midlands pal, Birmingham
 
I rather think that if you remove the DPF the car will fail an MoT.

Really? My understanding is the DPF catches the soot with diesel fumes.. And MoT test smoke levels, not soot levels within the smoke.

Please correct me if I am wrong..
 
The recent changes in MoT regs requires the factory fitted DPF to be present. Similarly with CATs. Even if the vehicle passes the emissions test if the CAT or DPF has been physically removed its a fail.
 
The recent changes in MoT regs requires the factory fitted DPF to be present. Similarly with CATs. Even if the vehicle passes the emissions test if the CAT or DPF has been physically removed its a fail.


I've read the latest technique with decats and DPF removals is having the removed, empty cats and DPF replaced around the straight through pipes :devil:


Also.. has anyone actually been failed due to no DPF or Catalytic convertor ? Not something I've heard of (in my research and limited knowledge of MoT's)
 
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The recent changes in MoT regs requires the factory fitted DPF to be present. Similarly with CATs. Even if the vehicle passes the emissions test if the CAT or DPF has been physically removed its a fail.

Not quite correct. DPF's can't be removed, but Cat's can on Diesels. Obviously they still have to pass emission test levels after Cat removal. Practically all post 2002 diesels running ok with the Cat removed should pass a fast pass when suitably warmed up.
 
I thought that any CAT or DPF that was originally fitted to the vehicle now needs to still be fitted to pass an MOT.
 
MoT Manual - Section 7.1.3 Exhaust System ------ On spark ignition engines that qualify for a full catalyst emissions test and all compression ignition engines, check the presence of catalytic converters and particulate filters.

Reason for Rejection ----- Missing Catalytic converter or particulate filter where one was fitted as standard

MOT testing manuals and guides
 
MoT Manual - Section 7.1.3 Exhaust System ------ On spark ignition engines that qualify for a full catalyst emissions test and all compression ignition engines, check the presence of catalytic converters and particulate filters.

Reason for Rejection ----- Missing Catalytic converter or particulate filter where one was fitted as standard

MOT testing manuals and guides


So its safe to assume to days of DPF & Cat Removal is coming to an end? :eek:
 
Some companies are asking customers to sign disclaimers ......
 

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