86 Hardbdy Falters When Warm

My 86 p/u Z24 2.4 always faltered if the accelerator was pressed too hard. I was out of town for a year and my mother had the truck smogged (California) and tuned. Now when I first set out with a cold engine the truck runs better than ever and does not falter when accelerator is pressed hard. I can drive forever without a problem until I turn it off and restart it before it has completely cooled (3 or 4 hours.) If I do not let the truck cool completely it is almost impossible to drive. It falters very frequently - almost as if some demon is kinking and unkinking the fuel line. I am not mechanical but I am broke and will need to try to fix it myself. A friend told me the rotor might need cleaning or replacing. Any advice would be appreciated.