How many pounds of carbon monoxide do cars produce?

According to the SMMT there are over 30 million cars on the road. Each car produces about 3,050 lbs of carbon/year give or take. (this is an average of 4, 6, and 8 cylinder cars that have been well maintained, weigh one ton, and drive the average of 12,000 miles/year. This figure also includes the rate of CO2 emissions as 5lbs/gallon) Therefore, on average, cars produce 915 X (10 to the 7th power) lbs of carbons/year! this is a loose estimate based on several assumptions, however all assumptions are educated and researched. hopefully some one will be able to give a more detailed answer than this.