❗【KEY POINT-Inductive pick-up】The inductive pick-up is essential for the timing light automotive. Clamp it around the No. 1 spark plug wire, ensuring the arrow points toward the spark plug. A: Only use timing light to test gasoline engine vehicles; The inductive clip should clamp on the NO.1 spark plug wire and the arrow should be pointing towards the spark plug; Check if the inductive clip is clamped in place (correctly).