Hard starting when it cools off or first in the morning

Hello, my is hard at starting when its cold or sits about an hour or two. I turned the switch to on and off about five times the fuel pump makes the same noise every time and still is hard at starting. So i know the fuel pump is okay. And i also cleaned out the throttle body and checked fuel filter and still acts the same. Could you guys please help me on what it could be? Thanks so much. Jimmy