When does a DPF regen happen?

[RMDrive]

Hi. Learning about DPFs and regens and Itrying to find out when a rergen happens. Is it at every opportunity? So if I did a long drive every day, would a regen cycle  happen every day? Or is it only when it's needed?

The car is a 2010 1.6TDI 105 Fabia. My missus only does a short run in in every day (~12 miles a low speeds and revs) so I'm making a point of getting it a longer run every couple of weeks. 

9 days ago, I took it on a 250 mile trip and 2 days ago it got another 50 mile spin. But today the DPF light comes on! Another quick run this evening got rid of the light but I can't understand why the light would come on so soon after 2 long runs.

 

Any thoughts?

 

[littleade]

While you drive the dpf completes passive regeneration, which on short trips won't be enough to burn off the soot. The next phase is the active regen which is either triggered by the soot level reaching a certain point or 600 miles since the last regen whichever comes first. This does not involve a dpf light and the normal signs are increase in tickover with the exhaust smelling a bit. If you fail to complete this regen then the fans will switch on when you turn off the engine. Assuming you have a cr engine you've reached the driver assist stage which means the car now needs help to complete the regen. If you do not complete this regen and get repeat dpf lights at some stage your car will go into limp mode and you will have to go to a dealer or find someone with vcds to do a forced regen. If there is nothing wrong with the car and you keep getting the dpf light it might be because the car doesn't suit your type of journeys. If you look on skodas website under the owning a skoda link there's a leaflet on dpfs which explins this in more detail. HTH

[iSamage]

I remember coming back from numerous 300-350 mile trips and the next day noticing an active regen with increased idling, hot smells, higher oil temp and fans running after shutoff only a day after getting home. Like said above, this only happens when the soot reaches a certain level. It could be just blind luck that it didn't regen properly on the long runs.

I have noticed however that now I'm running the engine in through 9k, it doesn't need to regen as often.

[The Plumber]

Previously had two Yeti's and an Octy with DPF's and despite doing a 72 mile round trip commute to work on open A roads, four or five days a week, I found the DPF's would fairly regularly regenerate, the second Yeti was particularly frequent in cold weather, mind I did not get any warning lights, just the sense of heat, the smell and high idle.

 

Don't naturally drive cars hard, so maybe even with a reasonable distance to cover daily, the DPF system didn't suite my style of driving. Now reverted to petrol, although I'd set out to get another diesel and beginning to think I might better off without the complications of a modern Euro V or upcoming Euro VI controlled oil burner.

 

 

TP

[RMDrive]

Thanks for all the help! Will keep and eye on this and see if I'm getting lots of lights.

[littleade]

From what you've said ask SWMBO if she notices the tickover is higher at around 1100 rpm when she switches the engine off and if the fans then come on as that will be a sign she's interupted an active regen. Repeat occurances of that would then lead you to get the dpf light come on. As above they seem to settle down once run in and the engines loosen up a bit-guess its because they don't have so much internal friction, so you use slightly less throttle. I had the fans a couple of weeks ago, so when I drove it next a couple of hours later I checked to see if the tickover was high once up to temperature then went for a nice drive to let it do its thing. Once tickover returns to normal its finished. So far that's thefirst one I've noticed this year, but obviously there will have been others so to me its not an issue. Good luck.

[silver1011]

Having a 65 mile each way commute I often notice my Superb chooses the last few miles to start the regen which then obviously I interupt when arriving at work or home.

 

It always completes happily during the next journey though.

[Lewisb1989]

I have had my Monte 18 months and done 14k init. Never noticed it do a regen or seen any lights on the dash. I do a 20 mile each way commute every day. Mixed driving averaging around 50-55mpg in the winter and 55-60mpg in the summer.