Diesel particulate filter cleaning

[BrumGalaxy]

Hi,

I'm looking for help with the DPF cleaning process on my Galaxy.

Yesterday I was driving when the car informed me that it was going to begin cleaning the DPF. However I needed to stop the car before the cycle had finished. When I started the next journey, the car informed me that I needed to drive the car 'now' to start the cleaning process. Once again, I had to pause my journey to drop someone home. When I continued my journey, the cleaning process didn't attempt to restart but the yellow 'check engine' warning light came on.

Today I've been driving the car for 30mins at 30mph+ in an attempt to start the cleaning process. However the car hasn't told me anything about the cleaning process and the yellow warning light has remained illuminated.

There seems to be no way that I can manually start the cleaning process. I'm wondering what to do next.

Before Christmas, the 'check engine' light came on during the cleaning process and remained on for a day after the process had finished. I booked the car into a garage but then the light turned itself off.

Any advice on what I should do this time?

Much thanks.

[TomsFocus]

If you can't clear it by driving, you will now need a garage to start a 'forced regeneration' with a diagnostic tool.

[BrumGalaxy]

Thanks.

The handbook talks about driving at 30mph+ for 10-20mins but I wonder if it would help to go at higher speed, 60mph+, for 20mins, before booking it into a garage if it doesn't clear.

[TomsFocus]

9 minutes ago, BrumGalaxy said:

Thanks.

The handbook talks about driving at 30mph+ for 10-20mins but I wonder if it would help to go at higher speed, 60mph+, for 20mins, before booking it into a garage if it doesn't clear.

You may not be able to drive at higher speed if limp mode has been triggered.  But yes, there's no harm in trying it.  Personally, I've always found giving them a hard boot on a motorway slip road can trigger a regen fairly reliably.  (Just make sure the engine is warm and you've got at least 10 litres of fuel).

You can tell a regen has started by the sound of the high speed engine fan running (leave air con off) and the engine note changes, it gets a bit rougher and grumbly.  Once it has started, then you just need to keep driving at any speed constantly until the engine note changes back again and the fan stops.  And in this case, until the light goes out.

[BrumGalaxy]

Thanks - that's really helpful. I'll let you know how it goes!

[DaveT70]

As Tom says,

Take the car on the motorway and drive normally for at least 20 minutes with at least half a tank of fuel.

Once 20 minutes has past and you know you are clear enough to maintain current speed, hold the car at 60 MPH, but in a gear low enough to keep the revs at around 3,500-3,800 RPM

Possibly 3rd gear?

Just keep at that engine speed for at least 10 minutes and it should force regen.

Once it's started regen, keep the revs high and every 5 minutes dip the clutch and hold at red line for 5 seconds to aid the process. It should complete within 10 minutes, try not to stop, if possible.

Late evenings are the best time to do this, when the roads are clearer, then you know you'll be able to maintain speed.

Remember, it's not vehicle speed that regens it's engine speed

[BrumGalaxy]

Thanks for the support.

I went to take the car for a motorway drive but the warning light had already turned off! I presume that, even though the car didn't flag it up, my earlier drive was successful in cleaning the filter.