Poor Gas Mileage at 65,000 miles on 2000 Chevrolet Malibu

I'm having the leaking manifold gasket problem now and poor gas mileage! just got down replacing the fuel pump! what next? How do I solve these problems?

Asked by for the 2000 Chevrolet Malibu
Which Engine do you have? I ask this because some of the smaller V6 GM engines have a pattern of leaking coolant from the mainfold. The only thing that you can do is to replace the gasket, which is about a 4 hour job plus the price of gaskets and coolant.