I add a quart of oil approximately every 1,000-1,500 miles. On the floor of my garage there is no evidence of oil leaking from the engine compartment and there is no evidence of leaks around the engine area. There is, however, evidence of something coming out of my car's tail pipe. On my garage floor there is black residue right below my tailpipe. The black residue feathers out like it is coming from my tailpipe.

Car operates really well and I always take my car into Volvo for service. I use all factory recommended fluids and parts.

I appreciate any suggestions on what might be causing my car to consume/burn so much oil. Problem has been going on for about 2-2.5 years and it seems to be getting worse.