2002 Chevrolet Malibu car cranks nostart

My 2002 malibu had been giving me trouble for a few weeks some days woldnt start I would crankan crank then finalley start now all it does is crank if it does start it only runs for few seconds then dies it sounds kinds rough when it is running an today when running I smelled something like fire looked under neath car a caytalac converter was cherry red like really hot within seconds so im thinking maybe its clogged not sure it has new crank sensor an cam sensor new battery new fuel pump an filter it sayd it getting fuel an fire hooked it up to tester an its saying code misfire even had module checked its good an new plugs put on me an my husband are at a stand still its our only car with three kids I need ur help plzz