Uncle Turbo gave you good advice on trying a different brand of oil. Sometimes this makes a difference. My brother bought a used 1977 Cadillac back in the early 1980s. It used a quart of oil every 900 miles. 150,000 miles later, it still used a quart of oil every 900 miles. Some engines use a little oil. To me, a quart every 1000 to 1500 miles is not excessive. My first car, a used 1947 Pontiac that cost me $75, used a quart of oil about every 300 miles. To me, it would have great to have only used a quart every 1000 miles.