We've got a 65 plate VRS (~150k miles), and having constant issues with the DPF regen.

After an hour and a half of motorway driving we get a DPF warning (I can't remember the message). If we stop at a services then the light goes away and we can drive for another hour and half before it shows up again.

Yesterday we drove for 5 hours (mostly motorway/dual carriage way). The light came on and we didn't stop; we then had the coil light flashing and have an engine warning light stay on. No obvious loss of power, so we're not in limp mode.

This happened once before; the garage read the code and it was something like too many failed regen attempts. So we were told to take it for a 30 minute drive and keep it 2500+ rpm and that cleared the warnings.

Is this the end of life for our DPF? It's so consistent that the warning comes on it feels like it's a sensor/electrical issue preventing the usual regen process; any suggestions on what's happening? (Car's booked into garage, but not until the 8th).

4 hours ago, DaveyK said:

This happened once before; the garage read the code and it was something like too many failed regen attempts. So we were told to take it for a 30 minute drive and keep it 2500+ rpm and that cleared the warnings.

Have you done that during your 5 hour drive yesterday?

I didn't - I had a car full, and was tired (5 days on a boat on the broads and I just wanted to get home). I plan on doing that tomorrow to see if it clears the warning.

I assumed a pretty consistent 70mph for hours would be enough; is that wrong and it will always need a high-rev 30 minutes?

The car has regular long trips (the weekly shop is the only real short trip it does), and it always throws this error at an hour and a half - could it be a sensor/electrical issue; or do I just need to rev it out every now and then?

5 hours ago, DaveyK said:

So we were told to take it for a 30 minute drive and keep it 2500+ rpm

8 minutes ago, DaveyK said:

I assumed a pretty consistent 70mph for hours would be enough; is that wrong and it will always need a high-rev 30 minutes?

What are the revs at 70mph in top gear? If below 2500rpm then you need to be in a lower gear to force a regen.

It's around 2000rpm - so I know not enough to force the regen, now that I have the warning light.

But is that really how this is supposed to work in normal day to day use? I would have assumed a normal long drive at motorway speeds would be what is expected during normal operation?

I understand if I did lots of short trips then I'd need to do something different to compensate for that, but if I cleared this warning and drove for an hour and half that dpf warning would come back on.

1 minute ago, DaveyK said:

It's around 2000rpm - so I know not enough to force the regen, now that I have the warning light.

But is that really how this is supposed to work in normal day to day use? I would have assumed a normal long drive at motorway speeds would be what is expected during normal operation?

I understand if I did lots of short trips then I'd need to do something different to compensate for that, but if I cleared this warning and drove for an hour and half that dpf warning would come back on.

If the load in the DPF has built up too high then no amount of driving will force a regen, in this case sometimes a regen can be forced with a diagnostic tool but in others a DPF clean (or replacement) is needed.

After 150k miles you're past the assumed design life of a DPF, which is around 120k miles, so really all bets are off without the DPF load data from a diagnostic tool such as OBD11 or VCDS.

Thanks for the insight - I'll take it out tomorrow and try and clear the warning, and then see what the garage says. There's no other DPF warnings when they've looked previously, but I don't know if they've specifically looked at the load data.

Any idea on the cost to replace the DPF on this? Is that even viable.

Had the same issue with my recently acquired 2016 diesel vRS with 144,000 miles.

DPF warning light came on when trundling in traffic on a very hot day. Fault cleared by my friendly garage - showed as "Intermittent DPF Pressure Sensor". Fault cleared and OK for a few days then,

Same fault cleared by garage but was shown a Hella sensor on the "upstream" side and the original Bosch one on the downstream side. Advised that they both ideally should be changed so booked car in. Incidentally, I was told by a friend who followed me one day at this point that there was quite a lot of blue smoke from the exhaust.

Before the work could be done the curly glow plug light started to flash with the original DPF warning light again and car was in limp mode.

Got the car back after two days restored to health. The garage told me it had recently had a new turbo fitted but the folk who did that work for a previous owner in Newcastle ignored a number of other faults including the almost choked DPF and an exhaust gas temp sensor that was almost burned away to nothing. They must have also reset the DPF "electrickery" to zero which meant it would not regen on its own. Anyway, two new Bosch DPF pressure sensors, a new EGT sensor and a forced regen later the DPF is now down to 4.3 gms soot (from 49 + gms); all the lights are out and it goes like a train with no smoke from the exhaust.

My advice to DaveyK would be to look for your local BOSCH specialist garage (who may specialise in VAG cars as ours in Sevenoaks does); they should be able to sort you out.