if something such as an engine or a fire sputters, it makes short soft uneven noises like very small explosions [= splutter]:
Suddenly the engine sputtered and stopped.
2 [intransitive and transitive]
to talk quickly in short confused phrases, especially because you are angry or shocked [= splutter]:
'What do you mean?' sputtered Annabelle.
—sputter noun [uncountable and countable]