2005 Ford Freestyle engine problems

I drove into a parking space, set for park. The car just shot forward and hit a wall. The engine riffed loud, for a few second. Could not redo the brakes. The wall was onle about 8 to 10 feet from me.the car was not in motion, because I just put it in park. It happen in a parkiong lot at cbs pharmacy. 1588 trancas street, napa, ca 94558 on march 14 2016 at 5:30 pm.there should be a police report. I had to go to the hospital, to check my back, because I had just surgery 3 weeks before, febr. 22 2016.

We started noticing the engine surge a few months ago whenever we shifted out of park or neutral. The rpm's jumped around 400-600 above idle and now are over 700-800 with the A/C on. So far, we have not experienced any damage to the vehicle. I took the vehicle to my local ford dealer, blackwell ford in plymouth, mi and was told I needed the throttle body needed replacement at a cost of over $800.00. The vehicle has 94000 miles on it and aside from that problem, we have been pleased with it.