What does a fluttering test light indicate when testing the ignition?

A fluttering test light when testing the ignition indicates that the pickup coil signal is intermittent. This means that the pickup coil is not sending a consistent signal to the ignition module, which is crucial for proper timing and operation of the ignition system. An intermittent signal may result in fluctuating or erratic engine performance, as the engine might not receive a steady spark at the appropriate times.

In contrast, a stable light would suggest that the signal is consistent and the ignition system is functioning as it should. This situation often points to issues like poor connections, a failing pickup coil, or other related problems. The fluttering effect specifically implies that there are interruptions in the signal flow, demanding further investigation into the pickup coil's integrity or its connections to the ignition system.