I had the dpf removed from my mondeo and deleted from software before it became illegal earlier this year, however i said nothing in the mot and it passed phew. The motor factors say they can get a non ford replacement for 150.

There are two rubber braided pipes that connect to either side of the dpf, im guessing that these sense a pressure difference across the cat and trigger a regen . I imagine it's something similar on the skoda, these pipes tend to get frazzled when hot like in slow traffic etc then they trigger a fault code leading to the dealer charging you a kings ransom for a replacement dpf. Im checking under my new superb to see if i can see a similar set up

Edited 17 November, 201411 yr by peterposh

One thing I have noticed on my MKIII Tdi Vrs, ( CR 184 bph ) the car regens more, around 600/700 miles. I think this is to keep the DPF clean all the time and not waiting untill it gets half full then having to regens.

 

Even after a long run it still regens. You would think a long run would be sufficiant for a regen but it appears to be milage related not how much is in the DPF

Most of my journeys are long runs and it still regens quite a lot.  Usually every few hundred kilometres which I thought was excessive but I had it checked out and apparently everything appears normal.  The burning smell is quite noticeable too

I'd never remove a fully functional DPF from a car, but when push comes to shove (eg., when my CR engined Superb finally coughs up 1 clogged-up DPF) damned if I will replace the DPF with another one, just so it can happen again another 150.000 km's down the road.

Most of my journeys are long runs and it still regens quite a lot.  Usually every few hundred kilometres which I thought was excessive but I had it checked out and apparently everything appears normal.  The burning smell is quite noticeable too

How do you know when it regenerates?

How do you know when it regenerates?

Slight drop in power (not overly noticeable) and the smell of burning (not in the cabin) however when you leave the car the fan will remain on due to the heat generated and this is usually how I know - the fan stays on for five minutes or more sometimes even on a longer run when the regen is trying to finish

BTW I was wondering how many of you guys were informed of the DPF when you bought the car from the dealer?  Did they explain its purpose, how it works, the fact that you should take the car up to motorway speeds  regular if you normally do a lot of urban driving etc.  My dealer made a point to explain it however I'd imagine this is not always the case.  I think it should be top of the list on any handover from a dealer where a DPF is fitted to a car!

Slight drop in power (not overly noticeable) and the smell of burning (not in the cabin) however when you leave the car the fan will remain on due to the heat generated and this is usually how I know - the fan stays on for five minutes or more sometimes even on a longer run when the regen is trying to finish

Ah.  That (hopefully) explains the smell of overheating and the fan staying on the other afternoon when I got home, I couldn't see any reason for it, oil and water temperatures weren't up and it had only been a short, slow run.

The tell tale sign when it's actually doing 1 is the increase in tickover to around 1000rpm. The 'fans' indicates you've interupted the regen before it could finish so expect it to have another go next time you're up to normal operating temperature.

Yeah, it takes a while for the regen to start as obviously the engine has to be at normal running temperature first.  My daily journeys are made up of a few runs of less then 30kms each time so most of the time the regen gets to start but rarely finishes and has to restart the next time I'm in the car.  On a motorway run it is barely noticeable.

The exhaust note can sound a little 'boomy' as well, at around 2000 rpm under partial throttle. The oil temp goes up a few degrees as well. The car can be a bit hesitant under light throttle as well. Mine consistently regenerates around every 300-320 miles, irrespective of driving style. Differential pressure across the filter will dictate the regen cycle initiation as this is a function of the physical amount of soot in the DPF.

 

Ash residue is usually what kills a DPF as this cannot be burnt off and accumulates over the life of the filter, this can be read via VCDS although it's a calculated quantity rather than something that's physically measured. 

The tell tale sign when it's actually doing 1 is the increase in tickover to around 1000rpm. The 'fans' indicates you've interupted the regen before it could finish so expect it to have another go next time you're up to normal operating temperature.

Right on the rpm/tickover they hold aprox 100rpm on a regen, But the fans coming on is not a sign of a interupted regen. When a regen is taking place the fans will come on as this is the norm, If we have to force a regen at work the cooling fans will come on everytime.

Ah. That (hopefully) explains the smell of overheating and the fan staying on the other afternoon when I got home, I couldn't see any reason for it, oil and water temperatures weren't up and it had only been a short, slow run.

Sorry if I didn't make this clear, but I was responding to the above post rather than making a general statement and what I probably should have said was if you get the fans running flat out when you turn off the ignition then you have interupted a regen as the car then works to cool the dpf down from its current higher than usual temperature, which I believe is a safety feature. Personally I've never noticed the fans going while a regen is taking place and the engine is running, but I've never purposely checked for this either so next time I get one I'll be getting some wtf looks when I pull over to see if you're correct!

What about the environment, global warming and peoples health ?

 

The Global Environment council met a couple of years ago in....... Bali

 

They all flew there in 200 tonne passenger jets, and NOT easyjet charters either

I hope the jets had their DPF's working properly

I know you're joking, but the light aircraft I fly use leaded fuel and have pretty much straight through exhausts. Because up in the air reliability is number 1.

Because up in the air reliability is number 1.

 

Unlike in our cars, it's not like when the DPF finally sharts the bed and your car loses all power and sais "check engine, workshop!" on the motorway with a tired lorrydriver behind you just about getting ready to take his mac and cheese out of his built-in microwave, while he's calling his wife on the phone, in the rain, at night, is in any way dangerous.

Absolutely. They should take reliability more seriously, but people like gadgets and ecomentalists get upset.

The Global Environment council met a couple of years ago in....... Bali

They all flew there in 200 tonne passenger jets, and NOT easyjet charters either

oh, that makes it ok to remove dpfs then.

I think the point was to show a little perspective.

 

Once replacing a DPF becomes more cost effective than it is today then the argument for DPF deletes will be resigned to those that are seeking outright performance gains, which IMO is not a justifiable reason.

 

Until then discussions on here about removing DPF's are quite often as a last resort to enable an otherwise perfectly reliable vehicle to continue in use, a view I happen to be in favour of on engines such as the PD170 in which it's relationship with it's DPF is proving to be less than amicable.

 

If the option of simply replacing it or upgrading to a CR170 was available to all then the DPF debates would be as dead as the DPF's themselves. Until then a little leeway is required on what is a very small number of vehicles.

I sympathise with pd engine dpf drivers, but took a £1000 hit myself with a pd Octavia scout with dpf, could have had it removed but opted for the legal option.

You can't justify removing it from cr engines, which is the subject of this thread. Firstly the cr / dpf engine is better designed and the dpf life is well over 100k miles. Secondly anyone buying a diesel car within the last 5 years should be aware of the existence of dpfs, the eventual need to replace them, and their unsuitability for short journeys etc.

People are doing it for performance reasons on cr's under the excuse of reliability based on earlier unreliable set ups such as the vag pd engines.

Edited 2 December, 201411 yr by classic

I wonder how much additional pollution the fabrication and manufacturing of dpf's creates and how much more of the earths depleting resources it uses due to the extra material needed over a straight piece of pipe.

Nothing is ever black and white, call me cynical but I doubt these calculations will be published as governments and car munipufacturers tick a box to show how they are doing there bit (and making more money) to save the planet.

Mine was always sooty pre and post dpf ! As was my dpf equipped PD Octavia and for that matter so is my petrol Fabia !

 

I am a detailer and do a lot of dpf equipped cars , I've yet to see one with a shiny tailpipe LOL

Mine has shiny tailpipes!..Never any soot on it..Just road dirt, which cleans off easily

my DPF "self regenerates", the tickover rpm goes up and it smells of burning

 

scared me the 1st time it happened

oh, that makes it ok to remove dpfs then.

 

they should lead by example instead of blagging a free holiday in Bali after burning 1000's of tonnes of kerosene at 30,000 feet