Can some one please explain to me roughly how long the warning light takes to come on while the car is doing it's usual thing (engine tone and exhaust tone change and using more fuel) my 13plate 1.6 hatchback seems to be doing all the usual things before the light comes on dash.

If I take the car for a run will it do the regen anyway or does it only occur when the light comes on? 

I have never really understood this, do I wait for the warning light?  Can  I take the car for a short burn and it will clear the exhaust filter anyway?  How will I know it has been done?  Other than waiting for the warning symbol to show

The light shouldn't ever illuminate unless there is an issue

If you are getting an engine management warning light come on, that will be an indicator that your DPF is blocked and that it has failed to regen. You'll need to go to the dealer to get it sorted if that happens. If it keeps happening, you've knackered your DPF (through failing to drive the car in a manner that will enable the normal regeneration of the Filter).

DPF Regen happens in the background, if working properly you do not get any lights or indicators of operation in the dash. It's supposed to be a transparent activity to the driver.

You need to drive the car in such a way that it has an uninterrupted 10-15 mins of driving at motorway speeds once a fortnight or so (or more frequently) to allow regen to occur).

As above, as a rule the car will sort the DPF out by itself without telling you, i.e increased engine rev's, stop start will not operate and usually, as with my Superb, I can smell it and feel the heat from under the car ... All I do is go for a blast up the road for about 4 miles and its back to normal... The light will only come on if it needs a "little bit of help" to do the job, so if you are getting no light all is well .... 

Long story short Mark, look at your RPM gauge at idle. Normal idle is about 750 RPM. When it tries to regen it goes to ~1000 RPM. As soon as you notice this, avoid shutting the engine down and try to drive down a clear road for about 3-4 miles at a 4th gear and about 40 mph. Failing to do that will make the DPF even more clogged and the car will complain with the warning light. Personally, I've never seen it go on.

Long story short Mark, look at your RPM gauge at idle. Normal idle is about 750 RPM. When it tries to regen it goes to ~1000 RPM. As soon as you notice this, avoid shutting the engine down and try to drive down a clear road for about 3-4 miles at a 4th gear and about 40 mph. Failing to do that will make the DPF even more clogged and the car will complain with the warning light. Personally, I've never seen it go on.

 

Exactly what I do in the Superb.. The Superb does about 150 miles a week, so I do get it quite a lot, the Rapid does 400 miles a week at motorway speeds so I expect that to be OK 

I mean the initial warning light where you see the filter and get the warning on display.  I have had this several times and taken the car for a run then and it goes off, it recently passed an MOT so I guess there were no issues bit this time it seems to be taking forever to give me the go for a run symbol on the dash.  I don't want to take the car for a run only to ind when I get back he light comes on.  As far as I know the light comes on to tell you to go for a run as the filter is 45% with soot.  There is no issue bit the engine note has changed and it is using  more fuel than it usually does.

I don't mean the engine management light or any other light other than the particle filter light. 

As already said - you should only be seeing a warning if there is a problem. There is no alert light associated with the DPF operating normally or carrying out a successful regen.

THIS ONE

That would be to alert you the DPF is blocked and can't regen.

You would never see that light if your DPF is working and regenerating normally.

Sent from my iPhone 6S Plus using Tapatalk, please excuse any typos.

Edited 17 July, 20169 yr by chrisgreen

It has come on a few times in the past and when I take the car for a run it clears from the advice in the hand book that is the correct thing to do

Yes, but the fact it keeps coming on is a clear sign that you are not driving the car sufficiently to enable the DPF to regen normally. Diesels need to be driven regularly and for more than a local run. They need motorway miles on a regular basis or the DPF will clog and eventually, won't regen any more and will fail early. That's an expensive replacement part and won't be covered under warranty.

Took the car for a 10 mile run along M61 as I got back the light came on so another trip cleared it,  The light comes on about every 1400 miles but this time it seemed a long time coming.  According to the hand book I am doing the correct thing.

A regen burns soot and converts it to ash which has less mass and less volume. This ash accumulates inside the filter and progressively reduces its soot capacity. So the time between two regens will always shorten exponentially as the years pass by.

How many miles do you have?

13 reg car brand new now has 9500 on clock. it actually worked out cheaper for me to get this diesel from Motor point than getting a new petrol form Skoda.  It is now just out of the 3 year warranty hence my concern about the regen not occurring as normal.  however it seems to be sorted now

Thanks

10k in three years would suggest your not covering the distances this car needs to clean itself, hence the fairly regular warnings. 

 

It may be that the DPF will prematurely fail which will be pricey, so you may be better considering a petrol for your type of driving.

 

 

As a side note I had issues with a DPF on a Yeti which Skoda didn't really understand but I eventually worked out that my style of fairly gentle driving and cold winter weather were the issue; the engine wasn't getting hot enough to do a proper clean. Cured the issue by fitting a lower front bumper grill cover during the winter allowing the engine bay to get a little warmer.

 

 

TP

As above - TP is correct, you are definitely not doing enough mileage to efficiently and effectively regen the DPF, prevent clogging and ensure summer fuel is flushed through when we switch to the winter mix etc.

3k a year is way too low mileage to warrant a diesel and in these days of DPFs and emissions control, is inadequate usage to keep the engine running efficiently. VW Diesel engines in particular need to be driven regularly and hard to get them to temp and consuming diesel at peak efficiency. Also, to trigger regen in the background (again, so you never get a warning light). Winter grill shields are well worth investing in, even in the UK. I had one for my diesel C4, made a big difference to warm up on my 70mile daily round-trip commute. Still needs regular miles though.

It really looks like you've bought the wrong car for your driving profile. For 3k miles a year a petrol would have been more appropriate. If you really want diesel, you need to consider an older, pre DPF car. Something like a mk1 or early mk2 Octy for example. But you'll be looking a banger-age diesel cars now if you want no DPF.

3000 miles a year is only 57 miles a week or 8 miles a day.

 

A big DPF regen needs a good 20/30 miles at motorway speed to complete a full cycle.

 

You maybe getting partial re-gens during your drivng cycles, but at such low mileage the engine needs at least 5 miles at a high RPM to get upto coolant operating temp, then a further x miles for oil... then once all these parameters are met a re-gen may then start.

 

One other option is to enable a forced regen and then do out for a long drive.

 

As you mention the M61, I would be in the mindset of thinking of having a day out in the south Lake District area, get some miles on the car up the M6 where it tends to be a clear run after Preston.

Edited 28 July, 20169 yr by RickTT

Hello guys , i've got the same issue with my dpf, car is in limp mode ( engine management,coil pack, dpf lights are on) at the diagnosis they said my dpf filter is blocked 47.2 grams and the limit is 45.. Can I clean it? Or i have to buy new one? Can someone recommend me any method to sort it ? Thanks

Hello guys , i've got the same issue with my dpf, car is in limp mode ( engine management,coil pack, dpf lights are on) at the diagnosis they said my dpf filter is blocked 47.2 grams and the limit is 45.. Can I clean it? Or i have to buy new one? Can someone recommend me any method to sort it ? Thanks

 

In ascending order of effectiveness:

 

a) Clean the old DPF. Needs cutting and welding. Will clog again soon.

b ) Get a new DPF. Costly but is the factory recommended method.

c) Gut the old DPF. Needs ECU reprogramming, passes optical inspection. You'll never worry again, you'll get quite a few Nm's and bhp's but also more noise and exhaust soot.

d) Get rid of thr DPF (and possibly the EGR) altogether. Needs a downpipe and ECU reprogramming. You will be fined if caught. Results slightly better than c).

 

I would probably go with c).

Edited 31 July, 20169 yr by eyegr

Thanks! I was thinking to buy new one .. But hard to find one!do you recommend any websites?

Or any garages for C in order, i live in canterbury, kent. Thanks

I normally buy DPFs and Cats from http://www.cats2u.co.uk

Doesn't currently have anything listed for the Rapid, but worth giving them a call. Usually very helpful.

Thanks! Does it worth trying to clean those 47 grams? From my old one