I agree with CJRomeo. Diesel runaway is a known problem of all modern turbo diesels - you can even watch it happen on YouTube.
The primary cause appears to be a failure of the turbo high pressure oil seal which then pumps lubricating oil into the engine, which it then happily consumes as fuel. The engine then revs uncontrollably until something breaks, or it drinks all the oil - and then it breaks anyway. Don't think the regen cycle has any blame in this.
P.S. Assuming it was the turbo that failed, please note that its a Garrett component and not Alfa's own, so for once AR don't have to take the blame!
Last edited by ukmike2008; 12-02-10 at 08:58.