Circuit/System Description
WARNING: This page is about a different variant/trim than selected.
The evaporative emission (EVAP) system uses a 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 switching valve
- EVAP leak detection pump pressure sensor
When the EVAP leak detection vacuum pump is ON and the EVAP leak detection pump switching valve transitions from vent to not venting, pump, position, there should be an initial vacuum drop followed by a vacuum increase on a good system. The diagnostic looks for a difference relative to the reference vacuum, either an increase or decrease. No vacuum change indicates a problem with the EVAP leak detection pump switching valve and a P2450 is set. The switching valve is integral to the EVAP leak detection pump assembly and is non serviceable.