DPF

[SGT Strev]

Hi has anyone removed there dpf and replaced with one of the straight thru options available

Cheers Sgt Strev

[mannyo]

No not done that, but from next year DPF removal may become illegal because if your car is fitted with a DPF from the factory it must be present for the MOT test, and you may fail a roadside spot check as the smoke pass levels for DPF equipped cars are being reduced.

You cannot simply remove the DPF, you'll also need to have a remap that takes into account the fact the DPF is not present and maps it out.

My PD140 is used for 90% short distance runs and has never had any problems with the DPF.

[Chubbs]

Hi has anyone removed there dpf and replaced with one of the straight thru options available

Cheers Sgt Strev

Hi

You'll find plenty of threads on the Octavia II forum re DPF removal.

Regards

Chubbs

[stevehg]

No not done that, but from next year DPF removal may become illegal because if your car is fitted with a DPF from the factory it must be present for the MOT test, and you may fail a roadside spot check as the smoke pass levels for DPF equipped cars are being reduced.

You cannot simply remove the DPF, you'll also need to have a remap that takes into account the fact the DPF is not present and maps it out.

My PD140 is used for 90% short distance runs and has never had any problems with the DPF.

Personally, I have seen no notifications of changes to emissions tests for compression vehicles. At the moment there is not even a check for Catalytic converters on diesels, so I doubt very much a check for DPF will be introduced in the near future.

Currently (and there are no planned changes) there is just a smoke test of diesel vehicles, with fast pass option. It's common for Euro IV, V, and VI compliant vehicles to not even register a reading on smoke test, let alone get near a fast pass failure.

So removing DPF, along with EGR is perfectly legal and is very unlikely to cause any issues with smoke test on MOT. I have a 2005 LR Defender with cat and EGR removed and it fast passes every time.

As far as I'm aware, ECU fuel maps are not affected by DPF and EGR sensors, so ECU will not need to be remapped. However, ECU will need to be re-programmed to stop sensor faults etc.

Cheers

Steve

[SGT Strev]

thanks very much as always for the advice :)

[infoschumi]

Illegal or not,if you remove it,the car will make a lot of smoke,it smells very bad(you can't stay near the rear of the car if it's idling) and the exhaust will make an ugly noise imo,like a broken turbocharger.The good part is that the engine will run very smooth and the turbo lag will improve a lot.

[shark_90]

If it's mapped properly it won't smoke. We have done scores of PD engined cars and many CRs too with zero smoke issues.

[vRS 170TDi Cork]

is this true also ? " it smells very bad(you can't stay near the rear of the car if it's idling) "

[Richf]

Cant see why it should be , the cat will still be in place at the end of the day

Not dpf 's i know but I had two cats on my last car (E320cdi) I removed them and fitted a stainless exhaust system and even with the remap the smoke was still only barely noticeable and then only when driving very hard

Since not all the exhaust gasses even go through the DPF I'd be surprised if the difference is that pronounced

But Mannyo is correct from next year a missing cat irrespective of emissions figures will be an mot failure, I have heard that DPF's will be added to this section.

See page 8 of this magazine

http://www.dft.gov.uk/vosa/repository/MoT%20-%20Issue%2050%20-%20May%202011.pdf

[stevehg]

But Mannyo is correct from next year a missing cat irrespective of emissions figures will be an mot failure, I have heard that DPF's will be added to this section.

See page 8 of this magazine

http://www.dft.gov.uk/vosa/repository/MoT%20-%20Issue%2050%20-%20May%202011.pdf

Sorry but you are wrong, see page 172 of the MOT inspection manual, issue date 1st January 2012

Cat check is just for spark ingintion engines not compression.

And as for stating... "I have heard that DPF's will be added to this section." Well that's just.....

[Richf]

Sorry but you are wrong, see page 172 of the MOT inspection manual, issue date 1st January 2012

Cat check is just for spark ingintion engines not compression.

And as for stating... "I have heard that DPF's will be added to this section." Well that's just.....

Feel free to post your source then i posted the one i could find on google since i heard about this a long time back

The exhaust system will fail the MOT if:

* Part of the system missing or excessively deteriorated

* A mounting is missing or damaged so it does not support the system

* There is a major leak

* The system is excessively noisy. (Mot'ers discretion)

Edited 21 September, 2011 by Richf

[stevehg]

Feel free to post your source then i posted the one i could find on google since i heard about this a long time back

Jesus, to save you the effort of further googling here is the inspection manual....1-1-12 Mot manual

No conjecture, no 'I heard this', just simple facts

Hopefully you'll be satisfied with this.

Cheers

Steve

[mannyo]

The key to the DPF failure is here, right in the manual you linked to. Without a DPF you will not be able to achieve this figure.

smoke levels is:

a. for vehicles first used on or after 1 July 2008, more than 1.5m^-1 for both turbocharged and non-turbocharged engines

The previous limits and that for older cars is double the figure above for turbo charged diesel cars.

[stevehg]

OK, so after you've read the docs, you now agree that it is not illegal to remove either the CAT or the DPF units from Diesels engines.

In addition, there is no planned MOT changes in 2012 that will change this.

So for your latest statement...

The key to the DPF failure is here, right in the manual you linked to. Without a DPF you will not be able to achieve this figure.

Sorry but this is NOT correct. Why do you keep making statements that are not factually correct?

The smoke test level you refer to for post 2008 vehicles in the new 2012 test is the identical to the existing smoke test fast pass level. Plenty of Euro II, Euro III, Euro VI and Euro V compliant veicles already pass the fast pass level. A large percentage of these veicles do not have DPF's

So as you can see, plenty of vehicles without a DPF pass the existing smoke test fast pass level. It's impossible to say that all post 2008 vehicles (so Euro IV or better) will fast pass with the DPF removed (if they have one!), however it is possible to state that it is likely that a large percentage will.

Also, just for clarification the MOT smoke test, tests exhaust gas density only. It does not analyse the gases and look at particulate levels like the Euro emission tests. Various factors affect exhaust gas density not just particulate levels.

I have no hidden agenda here, I personally think that when it comes to making statements about legal requirements, it's perfectly ok to correct them when the facts show that their statement is wrong. Especially when people are asking on a forum for advice.

Cheers

Steve

[roman.w]

My 03 plate had a reading of .78 at its last MOT after a bottle of Redex was thrown in.

[Cown]

And let's not forget, those of us located outside the UK, wont have any legal problems removing the DPF. Thx :-)

[infoschumi]

is this true also ? " it smells very bad(you can't stay near the rear of the car if it's idling) "

Regarding the smell,I'm saying it from my own experience.It's true that a good remap will handle the extra smoke,but I'm sure it won't make the car smoke-free.

[0ggy]

The only "smell" that emanates from the rear if the car is when the dpf is actually regenerating at a higher idle speed. Without the Dpf in place this won't happen, and therefor only normal exhaust fumes will be present, and no untoward nasty smells.