2007 Ford Freestyle fuel system problems

We have owned this car for just over a year. For several months now, we have been having problems with the car surging/lunging. It happens without any notice, and you have to slam on the brakes to stop it. Initially, I only noticed the problem when pulling into a parking space. The vehicle would lunge forward. In the last couple of months it has started lunging backward and forward, regardless of how fast I was going (pulling in, backing up, or driving down the highway at a steady speed.) once, the car lunged as I…

My freestyle sel vehicle's (6/2006 prod. Date) wrench light came on which is supposed to be for transmission problems. Car hesitates on shifting, especially downhill. In the morning a slight lurch is experienced when pulling off before car is warmed sufficiently. Car has 40k miles and has a 100k warranty so the dealer assessed the problem at a throttle body and put in a part order. The part needed is a non-water cooled one which is impossible to find until is goes into manufacture in december.