Avensis blue smoke

[Bluestreak5]

Hi folks, just joined the forum.

My problem is that my 11 plate Avensis Tourer 2 litre Diesel, has a habit, on a random basis of giving out loads of blueish smoke, usally when the car is not fully warmed up and I am accelerating in 2nd on local roads, people behind pull back as it is so bad, but other times overs weeks it behaves fine no smoke. the car  is still under extened warrenty, so going into main dealer next week but have a feeling they wont be able to replicate the fault any things I can mention to the garage when I get there to help them sort it? The car has done about 79,00-0 miles and dives beautifully even when giving out the smoke. I have noticed the car takes ages to warm up but when it gets to temp it stays solid mid range on the temp indicator.