Definitions of sputter:

• noun:   an utterance (of words) with spitting sounds (as in rage)
• noun:   the noise of something spattering or sputtering explosively
• verb:   make an explosive sound

  Example: "Sputtering engines"

• verb:   cause to undergo a process in which atoms are removed

  Example: "The solar wind protons must sputter away the surface atoms of the dust"

• verb:   utter with a spitting sound, as if in a rage
• verb:   spit up in an explosive manner
• verb:   climb awkwardly, as if by scrambling