View Here : Xc90 Oil Leak
My buddy has a Volvo XC90 with the 2.5 turbo 5 Cylinder and it has been consuming oil rapidly. He just changed the oil and put in 10W-40 Mobil-one Synthetic because he read the 10W-40 weight may slow the oil consumption down instead of the 5W-30 and also installed a new oil cap o-ring.
Yet, it goes through 4 qts of oil every 1000 miles. If you don't check it frequently, it suddenly is 'dry' and takes several quarts to bring back on the stick to full. There is a little puff when first starting of light smoke, then nothing out of the ordinary.