Circuit/System Description
WARNING: This page is about a different car, the 2019 Chevrolet Malibu. However, it is still accessible from the selected car via links, so may be relevant.
The evaporative emission (EVAP) system uses an EVAP Leak Detection Pump to test for system leaks. The EVAP Leak Detection Pump assembly consists of the following components:
- EVAP Leak Detection Pump with reference orifice
- EVAP Leak Detection Pump pressure sensor
- EVAP Leak Detection Pump switching valve
The engine control module (ECM) commands the EVAP leak detection pump switching valve to vent or not venting, pumping, position by a switch called a driver. The ECM monitors the commanded state of the driver and the actual state of the control circuit. If they do not match it sets a DTC. The switching valve is located inside the EVAP leak detection pump and is non-serviceable.