(T) Sedici random blue smoke

ok, the saga continues,I tried a regen after driving for 6 miles and it failed (engine temp too low)so i drove another 20 miles not getting home till dark.
I started a forced regen, smoke started fairly soon after and lasted about one minute (I think this is normal) and as it cleared sparks started coming from the exhaust, which i think may be burning carbon or rust due to higher precat/ dpf temps.
The precat and dpf being filters makes me think this is not from the turbo or engine.
Anyone know what the sparks are??

Depending on how many/much sparks there were that's probably kind of normal at the regen temperature, 600+°C, some carbon and crap being burnt off.
I had another regen today, they are still regular, every 200 miles...ish, every 6 days.

Yes I did not expect the smoke, but it was pitch black , so hard to see, I will await a daytime regen in a hundred miles or so.

Regen today in daylight, noticable smell of fuel, blue smoke in swirling car sized puffs on accelleration and not much different from before i replaced the precat, duration of regen was reduced by about 3/4, so only about 5 miles from start to finish, dissapointed after all that work.
Next I will try blocking the erg valve or replace the dpf...

That's strange, it solved the issue on mine. Are you 100% sure there is no exhaust gas leak between the turbo and new pre cat? You would see blue smoke coming from the coupling on a regen and will cause the smoke issue we experience.

What makes you think a gas leak between turbo and precat would cause blue smoke??

When mine came loose last week it smoked on regen, all nice and sealed and tight now, had regen yesterday all fine no smoke. There is also that video with the Vauxhall which has the same pre-cat setup with the leak and causing smoke.

The blue smoke from the engine compartment was quite visible btw

OK, nightmare to get the heat shield off again, so next regen I will pull over and see if there's any smoke in the engine compartment, thanks for the info.

Regen at 165 miles, large puffs of blue, but no real smoke trail. I pulled over and checked the engine around the heat shield, no smoke, reved but not a lot just at take off, its down to a level i can live with.
I may try cleaning the pre cat sensor or putting the erg blanking plate in??

That's strange that it's not cleared the smoke completely. If you can live with it that's fine.
Anyway I decided to change the Dpf on mine as well. The car was giving out bad fumes(the smell that is) wasn't great.
After market one off eBay £144 with 20% off.
The temperatures on regen have gone up, pre cat 731°, Dpf 649°, plus the terrible fume smell gone, and about 4mpg increase.

On the downside the small oil leak I had from the inaccessible oil seal behind the gear box has got drastically worse. The thing is, to take the gear box off and do the seal is mega work for me and garage cost would be a lot I think plus , would make sense to do clutch kit while it's off, 97,000 miles.
I changed the oil and filter, again! When I changed the Dpf and reset everything on mes.
If it's not one thing....

May consider dpf change, but i am not too bothered at this time of year, however I did get the clutch done as I had a fluid leak from the center clutch bearing, new clutch plus bearing plus labour £600 ( and the guy said it would have cost more had he known it was a 4x4, due to the transfer box removal).

I priced the clutch kit and oil seal to be done at local reputable garage, £535+vat(£640). I'm seriously considering doing it myself, full 3 piece LUK kit on ebay about £70+£22 for the crankshaft seal, that's £500 difference, may even do the dmf as it will have to come off. Just thinking about the pain after rolling around on the floor for 5 hours at my age! I'll get a couple more quotes, non vat.

So about six months later and only done 50 miles since last post, selling precat for £60 if anyone needs it, did not solve my smoke problem, may try replacing dpf once lockdown is lifted.