| Answer | Crossword Clue |
|---|---|
| WHIR | Run like an engine |
| PURR | Run like a charm, as an engine |
| REV | Run up an engine |
| SPUTTER | Run roughly, as an engine |
| IDLE | Barely run, as an engine |
| HUM | Run smoothly, as an engine |
| PURR | Run smoothly, as an engine |
| PURR | Run well, as an engine |
| TUNEDUP | Made run better, as an engine |
| PURRS | Hums like an engine |
| GUN | Rev, like an engine |
| CHUG | Sound like an engine |
| AIRCOOLED | Like many an engine |
| PURRS | Runs smoothly, like an engine |
| RARE | Like an inside-the-park home run |
