Cars are required to meet a specific standard when new - the law doesn't impose that standard for the car's entire life - in use

Not true. Manufacturers have to demonstrate long term compliance of their vehicles. That's why the ZDDP additive in oil has been reduced-it reduced long term cataytic converter effectiveness. The decision to reduce ZDDP is not one to be taken lightly because it is a superb Extreme Pressure lubricant.

The MoT protocol is largely a matter of convenience. Clearly it is impractocal to subject each car to a full New European Drive cycle every year.

Thre act of removing it isn't illegal-driving on a public road with it removed is. If DPF was optional, why won't dealers remove your DPF for you...?

Perfectly legal. Off road vehicles aren't subject to road vehicle emissions control. Can't see there being an insurance issue since the insurance risk factor hasn't changed.

Yes mileage will improve without the DPF. A 5-10% increase in consumption vs >95% reduction in soot? Depends on your view of air quality I suppose.

Similar sentiments were expressed when catalytic converters killed off lean burn petrol engines. But the >90% reduction in CO, HC and NOx was just too compelling from an air quality perspective.

DPFs are like affordable housing developments, a wonderful idea-in someone else's backyard!

CO2 just warms us up a bit - soot kills us.

The world probably doesn't really care about a bit of soot. The exception being ice covered regions. Ice has a high albedo ie it reflects most of the incident sunlight. Soot is a strong absorber of sunlight. So if soot settles on ice, it will increase the rate of melting.

As for us? Soot is only really a problem in large urban areas where the concentration of traffic is high. Do we need technical solutions, or should people with a sensitive disposition not live in the metropolis?! I must admit that I favour the latter...

I would happily retire to London if property wasn't so ridiculously expensive - there are so many amusements. I would hate to work or drive there, though. There is such vicarious pleasure in using my bus pass, and nowadays the air is so clean. So DPFs get my vote.

i had my dpf removed on my mazda 6 55 plate it was a nightmare problem

company called xxxx in london did the job

more info on their website (deleted)

Edited by Avant on 30/12/2012 at 22:19

Im not an expert here on these matters but from what I gather from endless googling is that:

* Removing the dpf will pass the MOT visual check as its not a catalytic converter.

* 99% of cars that have their dpf removed will PASS the emissions test

* You should really tell your insurance as many of the remaps to delete the DPF from the ECU will increase performance too.

The dpf collects soot, especially on start up, where traditionally diesel engines can kick out a fair bit. Once it gets to a certain % full and if the conditions are right, the engine performs a regeneration, to 'empty' the dpf. Where do we think that the gunk from the dpf goes when it regens? Yep, out into the atmosphere, the same place as it would of gone with no dpf.

Regarding people shouldnt buy a diesel if they aint going to do the miles or drive it in a certain way.... dpf issues are affecting many many types of car/driving type. Yes, those that pootle around town will probably have more issues, but even high mileage/motorway users are experiencing issues.

Most of the diesel engines in cars made in the last few years are made to be efficient and clean anyway. Its not the dpf itself that makes it clean, the dpf makes it slightly more cleaner.

All fuels that come from fossils will be bad for the enviroment. These fuels are also a finite resource. Driving a diesel that uses LESS of this resource may well be better for the planet and us inhabitants long term. Plus, if everyone stopped driving diesel, then the price of petrol would probably increase to cover the loss of sales. How so you ask? 1 Barrel of crude oil will produce x amout of petrol and x amount of diesel, they come from the same barrel. Take away most of the diesel production from that barrel and then the costs of refining that crude oil have to come from somewhere else... ie those that buy the petrol.

Well said .

Nice car - keep an eye on the timing chain though

You do know that your local remapper will remove the DPF and map out the DPF functions on the ECU for around 400? Best solution for anyone with DPF issues.

My local folks (London Remaps) are doing the service for the 2.0D Mazda 6 and other cars for £400. They remove the DPF pipe, knock the guts out of it, refit, then map out all the DPF functions. They'll also add an extra 30bhp if you want while they're at it for no exra charge.

But the cheapest way of sorting the DPF problem is to:

1. Remove the dpf pipe yourselves
2. Purchase a large bore drill (300mm long)
3. Drill out the DPF filter (minimum 100mm in diameter diameter)
4. Refit dpf pipe
5. Get someone to map it - costs about £250.

I notice the new parts of the MOT the inspector must look for all the parts of the DPF and check to see if it works this applies to cars were it was fitted as original equipment.Hope those who illegaly removed theirs have all the bits and the old program for the ECU.

Why are DPF's fitted? To reduce the small particles of soot that cause lung cancer.

Is it any wonder that governments and authorities are anti-motorist when some want to go back to the bad old days of lead poisoning and particle-ridden exhausts.

If you want to keep driving cars, you'll have to at least co-operate with those trying to make it tolerable.

Or are the DPF removers just as ostrich-like as the climate-change opposition ?

Edited by RT on 27/04/2013 at 20:34

Most people remove the DPF and replace with a piece of tube a definite MOT failure as for keeping the DPF and removing the inside and altering the program in the ECU people who do this are firstly idiots and secondly taking a very great insurance risk and could be subject to the DVLA deregistering the car but please take the risk.

Edited by Collos25 on 27/04/2013 at 22:06

I missed a word out the word "who" it read much better ,but you should have relised that you are so clever.

Most people remove the DPF and replace with a piece of tube a definite MOT failure as for keeping the DPF and removing the inside and altering the program in the ECU people who do this are firstly idiots and secondly taking a very great insurance risk and could be subject to the DVLA deregistering the car but please take the risk.

100% inaccurate. Please again give your source of information?

I suggest you read the new MOT directive very carefully.

I also have a C3 which is an 03 plate without a DPF, is that now going to fail ?

Daft and pointless comment. Since a 03 plate C3 would not have been fitted with a DPF (like many Euro 3 cars) it will never need a DPF. If you fitted one there would be no way to regenerate it etc since the ECU in the car would not know what a DPF was.

I also have a C3 which is an 03 plate without a DPF, is that now going to fail ?

Daft and pointless comment. Since a 03 plate C3 would not have been fitted with a DPF (like many Euro 3 cars) it will never need a DPF. If you fitted one there would be no way to regenerate it etc since the ECU in the car would not know what a DPF was.

Exactly, I'm trying to make the point that this thread if full of daft comments not backed up by actual informed facts. Still waiting for one of these posters to back anything up they have stated such as deregulation, running illegal, failing mot, invalid insurance. Anyone can come up with crap they just made up in their bedroom. One of your own lines "A brilliant command of the English language as well as law breaker."

suprisingly the americans seem to be far more ahead than us in the use of biodiesel.

but lets be clear, i dont mean straight vegi oil in your tank. i mean properly refined oil with all organic materials removed (animal fat can also be refined aswell)

some quick reading on bio usage.

http://biodieselmagazine.com/articles/1247/enhancing-the-burn/

quite interesting.

That's a website promoting biodiesel - of course they think it's a good idea !!

The purpose of DPFs is to reduce particulates - these cause cancer, so I'm all for DPFs.

if you research biodiesel on the web most info regarding bio will be direct from america,

to say they think diesels are for trucks only is acurate for the most part. but the vehicle industry there has only produced lesser quality engines compared to european versions. with the performance differences between 25yr old petrol or diesels, i know i would prefer petrol.

if you beleaive some of what you read, the quality of american diesel has been poor at best.

i have only foud reference to bio diesel (EN14214) having better lubricating properties than standard diesel.

but lots of references that fuel pumps still having rubber or nitrile seal which cant cope with bio fuel even though rubber should have been phased out years ago, this being the possible reason for b20 max for some manufacturers and b10 for others.

its a 2002 renault, the dpf is not like most i see on the internet, it is THE section of exhaust that runs under the car. so 1) manifold + egr. 2) cat converter. 3) flexi joint. 4) dpf. 5) rear section with single box (2'x4'x 5" approx) twin pipes behind nsr wheel.

been on parts site and checked part images, i have seen on you tube ect dpf being similar in size and shape to cat's, so is it really a dpf or an early attempt.

There's no conspiracy against biodiesel. It's just not as flexible as petrodiesel.

As far as the soot reduction is concerned, this is solely due to the fact that biodiesel is an oxygenated fuel. Petrodiesel could easily be oxygenated by adding a heavy alcohol to achieve the same result. The reason this is not done is because the prescence of oxygen in the fuel can cause the fuel to be thermally unstable in high pressure/temperature fuel injection systems. That's when deposits start forming in the injectors. If deposits form in the injector nozzles that will effect the spray pattern-and then you can kiss goodbye to meeting any emissions regulations.

The high boiling range of biodiesel isn't helpful either. Nor is the high viscosity when cold. Throw in the problem of limited availability and the uncomfortable question of competition with food crops and you can see why biodiesel just isn't the nirvana its proponents make it out to be.

Not when there's so much shale gas to be exploited. Sure, fracking isn't without problems, but there are fewer problems with that than there are with a lot of the alternatives.

i havent removed my dpf but would comsider doing it and a remap and any other polution reducing mods that help, overall.

What sort of pollution reducing modifications do you have in mind? It's easy to forget that the supposedly 'complex' DPF has no moving parts! They have a >90% trapping efficiency of most particulate matter.

Yes, there's a pressure drop across the trap and, yes, there is a fuel consumption penalty in regenerating the filter.

But the people who have problems with DPFs are the ones whose car use doesn't really warrant a diesel. You can spend a lot of time and money trying to solve a problem that isn't really that serious.

Out of curiosity, how much does WVO sell for these days?

I agree the process of making fuel would be an interesting project.

Out of curiosity, how much does WVO sell for these days?

I agree the process of making fuel would be an interesting project.

a localish garden center was selling 15 or 20 litre tubs for £5 each a while ago but have not looked recently.

there is masses of info out there and you dont need a white coat and clip board to do it, just some common sense and some simple skills. http://www.oilybits.com/biodiesel-processors/oilybits-biodiesel-processor-kits-60-and-120-litre/prod_622.html sell a good looking starter kit and explain the basics, but do a search for journey to forever, masses of info there and links to other stuff, mostly based in the usa but the science is still relavent. i have been mulling over for a long time, but got rid of my pug 405 (last of the mech fuel pumps) a few years ago, then put the idea aside. that said i dont know if i want to get rid of the laguna 2 for a car less safe (5* rating), so looking hard into the abillity to run it on bio i dont mind mixing fuel but 100% would be cheaper.

i should search this forum for relavent post.

well.. nothing particularily relavent there!

usual naysayers and those lacking knowledge of what biodiesel actually is..

(Post with link deleted)

Another pi55 poor attempt at selling some worthless snake oil.

Hopefully people on ths site are not as stupid as you think they are.

Edited by Avant on 13/05/2014 at 23:41

(Post with link deleted)

Do a proper independent scientific test and then get back to us.

Edited by Avant on 13/05/2014 at 23:41