what causes it to hesitate on takeoff

Can be many different things. You need to give more details how the car acts normally and what kind of maintenence you been doing for a better diagnosis. Start by checking or spark plugs. They may need replacing. I know doing so on my car made a big difference. Improved fuel mileage to 27 from 25 for about $10 in parts. Next check to see when you changed the fuel filter. If it's over 60,000k miles since the last change change it. Mine intermittenly caused the car to bog down because the dealer did not replace it at the recommended schedule. Also using cheap fuel can cause this problem. Try changing the station you get gas from. Lastly, your exhaust manifold. I just tightened the nuts down to specification after finding it loose and my MPG went up from 27 to 29 from the previous fix with the spark plugs. This fix also fixes other drivebility issues that can effect handling, braking and transmission functioning as well.

Thanks Steven ! Since the question was asked, the check engine light came on. I took it to the dealer down the street. It turns out it was the throttle control sensor,and the car runs great. I had someone(mechanic) tell me it might be the EGR VALVE. I was happy the check engine light actually came on as it lead to the real problem. Thanks for you response Mark C.

Glad your problem was simple to fix.