Leak Detection Pump System
WARNING: This page is about a different car, the 1997 Dodge Viper and 1996 Dodge Viper. However, it is still accessible from the selected car via links, so may be relevant.
The leak detection pump is a device that pressurizes evaporative system to determine if there are any leaks. When certain conditions are met, PCM will activate pump and start counting pump strokes. If pump stops within a calibrated number of strokes, system is determined to be normal. If pump does not stop or stops too soon, a DTC will be set.