Real Dictionary

sputter
verb: If something such as an engine or a flame sputters, it works or burns in an uneven way and makes a series of soft popping sounds.

sputter in American English
the act or noise of sputtering
to spit or throw out (bits or drops) in an explosive manner
to spit out drops of saliva, bits of food, etc. in an explosive manner, as when talking excitedly; splutter
intransitive verb: to make explosive popping or sizzling sounds
noun: the act or sound of sputtering
transitive verb: to emit (anything) forcibly and in small particles, as if by spitting

sputter in British English
noun: the process or noise of sputtering
verb