I'd start with changing the fuel filter on it then run some STP or Lucas gas treatment through it , use up a few tanks of fuel then replace the fuel filter again on it.Use some throttle body cleaner on it and check the plugs and wires , plus clean the connections on the ignition module where the wires plug into one by one with sandpaper and a wire brush, check the air filter and PCV valve on it too.
Hope that helps and best of luck.By the way if you've not treated the fuel and changed the fuel filter on it on a yrly basis or have run the tank low on fuel I'd sure start with those.
