I have the Mitsubishi Galant as mentioned above

I have the MItsubishi Galant as mentioned above. Recently I threw my timing belt and had to replace it and 8 valves. After this, the Idle control valve acted up. So I replaced the throttle body which includes the Idle control valve. Now the car will start up, warm up and then stop running, attempts to keep the engine going after this are futile. I am lead to believe that the car computer it bad or that the car needs to be reprogrammed. This car is 12 model years old, but for the most part has ran great. I am not in a positions financially to get a new car, but I dont want to spend much more on it as the timing belt incident cost me $1400.00. What do you think is actually worng with the car?