last month i hit a wall with my z

i actually got run off the road.... but either way since she hit that wall on the front right corner i've had issues with my car stalling out and now i can push the gas pedal down about 3/4 of the way and nothing happens, also when i do drive her i cant go above 50km/h... also every time i drive her for more than 5 mins i will stall out and have to pop her into neutral turn her over and go again, it is starting to drive me crazy! the last shop i took it too didnt really fix it (the mechanic was a moron

didnt know the difference between an intercooler and coolant....

) is there anyone who can help??? plz!