I've just had this....treg's in the garage (dealership) now.
I'm on 79k miles (3 years + 6 weeks
) and the problem began to manifest at about 45k. (So not identified or fixed at the 3rd service).
Started with light smoking when pulling away from stationary traffic and occasionally when accelarating out of that annoying 40mph queue. Particularly bad when urban driving. Also suffered occasional hickup on starting.
Today
the whole shebang gave up with blue smoke, loss of power, lumpy engine idling,.....and a big queue behind me. The worst thing was the sudden engine surge to 5000+ rpm with no foot on the accelerator! - PS: No one in front of me.........luuuucky!
It appears VW knew of this problem back in Jul 08 (probably earlier) when they issued a Tech Warning Report to dealers of these symptoms that Touareg and Phaeton 3-litre V6 engines might be experiencing.
It's the injectors and can be found on a simple diagnostic check. Result for me? To get the car out of the garage: a ?2,500 bill....6 weeks out of warranty!
Well that's the start of the story......fully VW serviced and MOT'd on the button, yet I told the dealer of the problems as they developed and I challenged them on emissions at MOT....told "no problem".
I suggest you get it sorted now....it's not pretty when it really starts to blow, AND you'll feel a real prat driving at 30mph belching black smoke trying to get back to your dealer. Good Luck.