go to and autozone or any other parts store and see if they will scan your truck for codes provided your check engine light is on....im assuming it is, if your engine has a miss.......
ALSO
check wires see if one got burned on the exhaust manifold.......
mite need to replace wires and plugs if there old......
check to see if the wires are crossed....mite be getting spark jump.....
when was the last time you ran injector cleaner threw the fuel system?... if you don't know when i would do it.....
when was the last fuel filter replacement?....i know they are notorious for fuel filter issues....so if you don't know replace it for sure......
hope this helps!