DPF delete

[alexis.jones]

Is this a good idea?, what are the pros and cons and will it make any difference to the performance? Thank you in advance

 

[flango]

easy short answers, yes good idea, removes potential DPF problems, car will produce a little more exhaust smoke, car will need remapping to cater for DPF removal.

Now becoming a very common mod as people don't want the cost of replacing the DPF which can be expensive

 

[Sp!ke]

Will the new MOT test changes have a beraring on removing DPF or secondary cats I wonder?

Its not clear to me whether it might be a problem or not.

 

[whitenemesis]

AFAIK, Anything that increases a car's emissions (C0/CO2) from the manufacturer's spec is a fail. That would also include remaps..

 

[Sp!ke]

Thats how I interpreted the changes too. I am tempted to do one of Ollys secondary cat delete but concerned that it could cause me problems win future with these new changes.

 

[bolide]

AFAIK, Anything that increases a car's emissions (C0/CO2) from the manufacturer's spec is a fail

Age will do that as well. There must be a tolerance otherwise every car will fail

With proposed changes to the MOT test, such as mandatory-working ESP, etc, older cars are looking more and more attractive every day!

Nick Froome
the independent Mercedes Estate specialists

 

[alexis.jones]

easy short answers, yes good idea, removes potential DPF problems, car will produce a little more exhaust smoke, car will need remapping to cater for DPF removal.

Now becoming a very common mod as people don't want the cost of replacing the DPF which can be expensive

So the remap i have had just done will have to be changed?

 

[flango]

So the remap i have had just done will have to be changed?

If you remove the DPF then most probably yes, but I would check with who mapped your car as every map is different.

 

[Alex Crow]

It is a good point about possible future MOT test standards, it may well be the case that cars supplied with DPFs when new, will one day have to pass a much stricter particulate emissions level.
Think on.

 

[Doodle]

Thats how I interpreted the changes too. I am tempted to do one of Ollys secondary cat delete but concerned that it could cause me problems win future with these new changes.

As Nick mentioned, the SL is almost certainly too old to qualify for any of this new legislation so there's nothing to worry about.

Mine still breezes what tests they do apply for emissions.

 

[Sp!ke]

I'm not so sure its that clear cut. The tester will look for modifications and if a DPF is removed its pretty obvious something has been modified.

There is no cut off point for these changes... basically if it was fitted when new then I suspect it needs to work.

So if it is obviously apparent your cats have been removed then depending on the tester, it could be put through as a fail.

 

[Doodle]

I agree, I think it is pretty clear cut on newer vehicles. But for older stuff, especially if they don't see a lot of them, will be harder to draw the line.

My MoT station probably only sees one SL a year - mine. Unless they are intimately familiar with the marque how can they say with authority what should or shouldn't be there?

 

[bolide]

I'm not so sure its that clear cut. The tester will look for modifications

I don't think that's the purpose of an MOT tester. He looks for safety-related matters and, increasingly, conformation to regulations

Most of the tests are visual - does the number plate conform to regulations, does the ABS light extinguish with the correct timing, etc - but the rest will be done electronically

What's the point in debating the contents of a catalyst can when the required result - an emissions test pass - is done electronically?

If the DOT wants to upgrade MOT testing to encompass verification of systems like ESP they will either have to upgrade every MOT station in the UK or rely on the onboard diagnostics on the car for a pass or fail

Nick Froome
the independent Mercedes Estate specialists

 

[alexis.jones]

So basicaly it wont be worth risking. Any other ideas to help with performance then?

 

[Sp!ke]

Well if half of the exhaust has been chopped out and replaced with something in stainless steel with no centre silencer or secondary cats it should be pretty obvious even to the most gormless MOT tester.

 

[flango]

We're all summising again The current VOSA ruling is it must pass the emissions specification for that vehicle as given by VOSA and uploaded into the emissions testing computer. Diesels must pass the metered smoke test. Other than that it doesn't matter if it has a cat, dpf or not

Theres currently a lot of debate between the MOT trade users group and Vosa on Cat and DPF deletion and remaps. The main one is remaps and the extra work it would cause to check ECU maps against a manufacturers map. It's already done for insurance purposes but time consuming.

My bet you won't see any changes to the current testing set up for a very long time. The biggest change nobody as mentioned yet is that in the very near future all MOT lanes will be fitted with cameras linked through the VTS direct to VOSA so they can check exactly what is on the MOT test lane at any one time and that the vehicle matches the details logged on on the VTS

 

[Sp!ke]

I don't think that's the purpose of an MOT tester. He looks for safety-related matters and, increasingly, conformation to regulations

I would agree with this historically but the new changes suggest something entirely different sighting even remaps as a fail.

 

[artyman]

There was an item on Watchdog last night about DPF filters clogging on cars used in town. Interesting to see how this goes, it seems that cars are getting a little bit too clever for their own good these days.

 

[Deleted member 37751]

Well if half of the exhaust has been chopped out and replaced with something in stainless steel with no centre silencer or secondary cats it should be pretty obvious even to the most gormless MOT tester.

Just fix a plastic tray under the car, the testers are not allowed to remove anything to have a look.

I was talking to an MOT tester the other week and he was on about a Ferrari that he tests (360 iirc) and it has a full length underbody plastic tray, it takes him about 15 minutes to test the car because he's not allowed to touch it.

 

[brian c]

DPF Removal

Why not just have the dpf cleaned? Protec Germany have two products which can be used. Where are you I may be able to point you to an indi who will help