SYSTEMS AND METHODS FOR ONBOARD CANISTER PURGE VALVE FLOW MAPPING

Methods and systems are provided for indicating a presence or absence of degradation in a vehicle evaporative emissions system, where degradation includes a restriction in the evaporative emissions system and/or a source of undesired evaporative emissions. In one example, a method includes, under conditions where an engine is not combusting air and fuel, applying a pressure from the evaporative emissions system to an intake of the engine, and indicating an absence of degradation in the evaporative emissions system based on a test flow in the intake of the engine being within a predetermined threshold of a baseline flow obtained at an earlier time via applying the pressure. In this way, a presence or absence of degradation may be indicated without relying on engine operation.