Hi not sure if anyone has seen this before, but during the DPF cycle on my 1.6TDI greenline, i get whitish smoke from under the bonnet.

Only during the DPF, no other time, I don't have any warning lights, and I have checked the engine codes with my Autel Diagnostic tools.

 

Totally lost on this one.

 

I do have a video !!

 

https://photos.app.goo.gl/dnBr9PQ3wfccHZD58

 

its on my google photos.

 

many thanks

Mark

 

Welcome.

 

Do not mess about then. Lots of heat there and likely oil from someplace. Get to a mechanic and find out from where. 

I have already ! they couldn't find anything, I might try a different garage. oil sounds most likely. although there isn't any drips, or anything in the engine tray. I suppose it doesn't need to be a lot.

 

Cheers

Mark

Are you losing any coolant?

Hi yes, !! very slowly forgot to mention that, but I do think I am loosing it during DPF if that's possible ?? the smell of the smoke could be burning coolant, its a weird smell. !

Where would it be coming from then if it was coolant,  ???

 

I just replaced my expansion tank cap, as i thought that was the cause, the mechanic said the engine was bone dry, but not sure i trust what he said.

 

Thanks

Mark

 

 

A pinhole in a hose close to the DPF would be one possibility. I had a coolant leak once that sprayed a tiny jet onto the exhaust manifold of my mk2 Golf.

Dense white smoke coming out of the bonnet edges had me reaching for the fire extinguisher before opening the bonnet to see what was going on.

Might be that the hose only gets hot enough and soft enough to leak during regens, making it a bit hard to observe at other times. 

I guess the heater matrix hoses might go near DPF, not sure what else.

Could also be a coolant leak into exhaust via the EGR cooler, plus an exhaust leak at, perhaps, the flexi joint after the DPF. Again, might only be happening or apparent during a regeneration cycle when everything is so much hotter.

 

Edit: On second thoughts, the exhaust gases going through there are on their way back into the engine, not on their way out, so I think that makes it unlikely to give the symptoms you're seeing. 

Also, EGR function will be inhibited except at the end of the regen cycle.

Edited 30 January, 20251 yr by Breezy_Pete
Correction ?

Hi This has been solved, so the Adblue injector is water cooled, and during a DPF cycle this leaks and was causing my smoke, the coolant being that silicone based stuff does give off a weird smell. They replaced the injector and the hose , all sorted. !! No more coolant leaks or smoke during DPF cycle.

Hope this information helps someone else