エンジンをふかす

expression, godan verb (-su)

rev an engine; race an engine

Used when pressing the accelerator to increase engine RPMs, often while stationary or in neutral.

• 彼かれは信しん号ごう待まちでエンジンを吹ふかしていた。

  He was revving the engine while waiting at the traffic light.

• バイクのエンジンを吹ふかす音おとがうるさい。

  The sound of revving the motorcycle engine is noisy.