Skoda Superb Engine Fan Running (even when car hasn't been used)

[Lucas_R]

Out of interest - do any of you know how often the DPF will regenerate? Is it something that only happens once in a while (or takes a while to build up before a regen is triggered?), or is it actually something that can happen everytime the car is driven if conditions are right?

Different engines will need to regenerate at different times, but as a rough guide, my SQ5 with the V6 TDI needs to do a regen every 450-500km or so with our type of driving, but if driven solely on the motorway the soot accumulation is much slower, so it would be every 700-800km or so. With urban driving and constantly being on and off the throttle, the soot accumulates much more quickly.

For a very small outlay, the VAGDPF app and Carista dongle as mentioned in my previous post would be a valuable tool and will pay for itself in no time. Much more convenient than VCDS and the information is displayed in a way that makes it basically foolproof to misunderstand.

Ahh, almost forgot - so if the car has exceeded 100% in terms of DPF soot level, and has tried on several occasions to do a regen but has been interrupted (eg engine turned off) then it will go into a soft limp mode (may or may not show a light on your dash at this stage) but basically it will cease even trying to initiate a regen. This will require a manual regen triggered with VCDS or Carista. But if the soft limp has gone on for too long, it may require a trip to the mechanic to have the DPF cleaned manually (either with chemicals sprayed into it or removal of the DPF and cleaning with high pressure water).

In my case, the soft limp mode went on for too long, mechanic could not trigger a manual regen, resulting in a full on limp mode shortly after with absolutely no power (seriously dangerously slow - absolutely absurd how slow the car was) and I had to physically remove the DPF and flush them out with high pressure water, before using VCDS to reset all of the DPF parameters (basically telling the car that a new DPF has been fitted).