T6.1 Beach smoke

[davejmulholland]

Hi All,

I have a 2019 T6.1 diesel 4 motion, 110k km's.
Had been driving for an hour today, fully loaded for summer hols, going uphill 100km/h and a weird momentary bird/frog noise from the front followed by a loss of power for less than a second and a cloud of black smoke out the back. Didnt stop, no flashing lights and carried on as usual, running smoothly.
Carried on for another 300km then the same thing again.
Went straight to VW garage and they said if there are no warning lights the computer wont show anything.
Van is running smoothly as usual now.
VW garage said but good diesel in ( I did go to a cheaper garage to fill up this morning). Only other thing to note is that we don't do long trips very often so I wonder if engine was just spitting out accumulated rubbish?
Any ideas?

Thanks,
Dave

 

[Perfectos]

Edit - 2019 T6.1 ?

Sounds like a partially blocked DPF or CAT clearing.
whilst going up hill the AD blue dosage is increased to reduce Nox from the exhaust.
I've seen it on a non ad blue T5.1 before with an orange DPF light on, hard driving and droping quickly down through gears to increase Revs and increase exhaust flow caused a quite dramatic clearance (black puff of smoke) , orange light immediately went out !

Could also be a combination of various factors, EGR clearing out the pipe work, gunk built up from short journeys, but unlikely to be purely EGR as this should have been fully closed at high operational temperatures.

The engine will have reached a proper working temp and will have been working hard with good pressure built up in the exhaust system, all that helps the long term gunk built up from short runs get out of the system. (Burns off) essentially this gets caught in the DPF , to be burnt off during Regen, then when the DPF clears it should be graduated, but it can be dramatic if through pressure is sufficient

Are you aware of the Regens recently? Did the black smoke coincide with Regens (every two hours of driving )

Keep an eye on it if it does it again, is it during Regen?

Is it running sweetly, pulling well and sounds normal ?

 

[davejmulholland]

Edit - 2019 T6.1 ?

Sounds like a partially blocked DPF or CAT clearing.
whilst going up hill the AD blue dosage is increased to reduce Nox from the exhaust.
I've seen it on a non ad blue T5.1 before with an orange DPF light on, hard driving and droping quickly down through gears to increase Revs and increase exhaust flow caused a quite dramatic clearance (black puff of smoke) , orange light immediately went out !

Could also be a combination of various factors, EGR clearing out the pipe work, gunk built up from short journeys, but unlikely to be purely EGR as this should have been fully closed at high operational temperatures.

The engine will have reached a proper working temp and will have been working hard with good pressure built up in the exhaust system, all that helps the long term gunk built up from short runs get out of the system. (Burns off) essentially this gets caught in the DPF , to be burnt off during Regen, then when the DPF clears it should be graduated, but it can be dramatic if through pressure is sufficient

Are you aware of the Regens recently? Did the black smoke coincide with Regens (every two hours of driving )

Keep an eye on it if it does it again, is it during Regen?

Is it running sweetly, pulling well and sounds normal ?

Hi, thanks for all this info.
I have never been aware of it doing a regen, but what you describe sounds exactly like that's what it was doing.
We had run the tank to quite low in the morning too, maybe there was more gunk than normal.
I'll keep an eye on it and be back on here if it keeps happening.