| Answer | Crossword Clue |
|---|---|
| SPUTTER | Bad sound for an engine |
| CHUG | Sound like an engine |
| CHUG | Sound of an engine. |
| DRONE | Sound of an airplane engine. |
| PUTT | When doubled, an engine sound |
| PUTT | When repeated, an engine sound |
| knockless | of an engine, bearing or fuel, producing no knocking sound |
| throatier | (of a sound such as a person's voice or the noise of an engine) Deep and rasping |
| throatiest | (of a sound such as a person's voice or the noise of an engine) Deep and rasping |
