Leak Detection Pump (LDP) EVAP System
The leak detection pump (LDP) is integrated into the EVAP system and can have two functions. The LDP can:
- Pressurize the EVAP system and detect a drop in pressure that would indicate a leak.
- Function as the EVAP Canister Vent on vehicles that do not have a separate EVAP Canister Vent.
The LDP is a vacuum-driven, ECM controlled, diaphragm pump. In order to operate, the engine must be running and vacuum applied to the Vacuum Switch.