2001 Other Mazda Models my engine do something wrong

Engine problem
2001 Other Mazda Models 6 cyl Two Wheel Drive 128000 miles

Hi, my engine do something when is cold and I start it its start to jump and make little noise like sss sometimes turn off itself I wish to someone help me, so I just check all houses, the egr valve I change already but still once it get warm just work normally, could you help me with that is a MAZDA TRIBUTE 2001 thanks.