Related Clues:

• Reek
• Worrisome engine sound
• Cat or engine sound
• Train sound
• Run smoothly, as an engine
• Run well
• Ricochet sound
• Kitten's call
• Sound of tires on the highway
• Contented sound
• Machine sound
• Revving sound
• Sonar pulse
• Contented tabby sound
• Make music, in a way