Quote Originally Posted by stanzz View Post
... oh, i did notice that my car had burned or leaked a few quarts of oil from my last oil change, about 3 months ago. there is no leak at the drain plug. help!
Losing a "few" quarts of oil in 3 months would normally be a lot bigger problem than poor gas mileage (although the 2 could very well be related symptoms from the same problem). Do you see any oil on the floor, in the engine compartment, or is there any blue smoke? What's the history of the oil loss (sudden, or slowly increasing over time), and also the full maintenance history of the vehicle.