Is it normal for mpg to be low during a test drive?

Don't rely on the vehicle's computer to tell you the gas mileage. The computer figures gas mileage based on engine load and vehicle speed. To get an accurate measure of gas mileage you need to do it the old fashioned way. With paper, a pencil, and a calculator. When you fill up, set the trip odometer to zero. At your next fill up write down the mileage on the trip odometer. Once you've filled up write down the gallons it takes to refill the tank. Divide the gallons into the mileage and that's your true gas mileage. For example, 300 miles divided by 15 gallons equals 20 miles per gallon. Different people get different gas mileage results as well because of different driving habits. When I was young and I'd drive the family pick up truck I got around 10 MPG. When my Father drove the same truck he'd get around 20 MPG. Same vehicle, different drivers. Hope that helps! Jim