What device is used to time the ignition in an engine?

A timing light is a specialized tool used to measure and adjust the ignition timing of an engine. It works by producing a flash of light that allows the technician to see the timing marks on the engine's harmonic balancer or flywheel while the engine is running. By pointing the timing light at these marks, the technician can determine whether the ignition timing is set to the manufacturer's specifications. If adjustments are necessary, the technician can make those changes to ensure optimal engine performance and efficiency.

In contrast, a timing belt is a critical component that connects the crankshaft to the camshaft, ensuring that these parts rotate in sync for proper engine function. A synchronizer is used to keep various engine components synchronized but does not measure timing. An ignition tester checks for the presence and strength of the ignition spark but does not directly assess or adjust timing. Thus, the timing light stands out as the device specifically designed for timing the ignition in an engine.