please help just bought a 97 civic and already problems

well i just bought a 97 honda civic automatc and already im having problems with it. actually just one problem, when i let go of the gas the engine rev's up. any idea why? i dont have a clue. if its the transmission i will be pretty upset, but i just hope its just something simple. and suggestions will be great. thanks in advance.

could be the tranny, could be a throttle body issue. check the throttle cable for over tight, the throttle body position sensor (TPS), the throttle spring's tension. vacuum lines, make sure they r all hooked up. also, the idle air control valve (IAC). really could be a number of things.

how high does it rev? is it a steady rev or does it jump straight up really high? It could be something as simple as the gas pedal just getting stuck. y7ou have to get into exacts for people to be able to diagnose the problem.