This is where Reuse comes into play. Factoring in all this energy use it may actually be better to buy a higher mileage used car than a brand new hybrid. By keeping an existing car in service that has slightly lower efficiency than a brand new one the net energy use could still be lower. However, the equation is not even as simple as all that. A ten year old car that gets 30-40mpg may actually pollute a lot more than a new car. Emissions standards have tightened over the years. And, as a car wears, the emissions typically get worse. If you choose to go for a used car, make sure it has been well maintained and that the emissions control equipment is in proper working order.
[Source: Wired Blog]