What characteristic of Sniffle Valves indicates a potential malfunction?

The characteristic of active dripping of fuel from Sniffle Valves serves as a significant indicator of a potential malfunction. Sniffle Valves are designed to vent air and prevent fuel spillage during various operational conditions. When functioning correctly, these valves should allow air to escape while ensuring that liquid fuel is properly contained within the system.

If there is active dripping of fuel, it suggests that the valve may not be closing properly or is otherwise compromised, leading to unwanted fuel leakage. This can create safety hazards and operational inefficiencies, indicating that immediate investigation and maintenance are required to prevent further issues.

Other characteristics like rapid opening and closing or excessive noise may suggest operational concerns but are not definitive indicators of a malfunction. Similarly, failure to vent air can be problematic but could stem from various other causes not directly related to the Sniffle Valve's integrity itself. Active dripping, however, directly signals that a malfunction is likely present.