I have an automatic/tap shift with several new parts that have been replaced in the car, including the engine, but things just aren't completely running properly yet. The car starts, but only when I put the car in neutral. Once the car has started the rpms rev up and down and fluctuate pretty consistently. The gears don't seem to be responding, or even completely going into gear whenever I try putting the car in drive. The accelerator is also not very responsive...instead of just tapping the gas pedal I have to press further to the ground in order to get a little rev in the engine. I'm not sure what the problem could be...my transmission is not old (I don't even have 150k on the car) and hasn't been tampered with. Please give me in some insight if you have any!!! It would be a huge help to have some other comments/speculations. Thanks!! 
