MK 2 Leon High Revs. possible DPF?

[cmscotland]

I've got a 2011 1.6 tdi and noticed when arriving home today after a six hour drive that the engine was making a strange sound when releasing the clutch and as I made my way through town (about two miles from the motorway) towards my house that on the two occasions I stopped, the engine was revving at around 1000/1100 rpm . If this was a regeneration cycle does anyone know if this should normally happen during the six hour drive (Motorway-Cruise Control-65-70MPH)?

I thought the car would have carried out a passive regeneration during this time? I'm thinking it may be DPF related as there was a slight burning smell from the engine when I shut it down. Any thoughts on the issue gladly welcome.

 

[Nath.]

It probably was doing an active regen. It will do passive regeneration whilst on a long run but it will still need to do an active one when the soot loading hits the level to trigger it. The thing is that the car isn't intelligent enough to know to do an active regen just because you're on a long run, it will only do one when the soot level triggers it and in your case it was when you were almost home (sod's law)

Your soot loading was probably almost at trigger point at the start of your 6hr drive. Due to passive regeneration it was still almost at the trigger point when you were almost home. Passive regeneration doesn't always actually reduce soot load, mostly it just burns off what would normally be collected and in doing so keeps the soot load at status quo. As you slowed down to town speeds as you were almost home passive regen stopped and your soot load increased a little and triggered a passive one.

This has happened to me a few times now.

I wish there was a regen button that you could push when you know that you're on a long run to force an active regen whatever the soot loading and totally clean it out.

 

[cmscotland]

Cheers Nath. I think like you say it's a case of sod's law with this one. A regen button would be ideal

 

[Benzy]

What's the difference between passive and active?

On my way to work (1 hour motorway) my car quite often will do something which makes the engine sound a bit rattly, and also gives me a huge flat spot and lack of power, but idle revs stay the same.

I've always just assumed that it is doing a mini regen of sorts and I have never seen the dpf light come on so I guess it can't be doing a full one?

Sorry for hijacking