Monte Carlo V6-204 3.4L DOHC VIN X SFI (1996)
Evaporative Emissions Vacuum Switch: Description and Operation
EVAP Solenoids
Numbers in text refer to image references.
DESCRIPTION
The EVAP Vacuum Switch (2), is used by the PCM to monitor EVAP canister purge solenoid operation and purge system integrity. The EVAP Vacuum
Switch should be closed to ground with no vacuum present (0% EVAP Purge PWM). With EVAP Purge PWM at 25% or greater, the EVAP Vacuum
Switch should open.
An incorrect EVAP Purge system flow should set a DTC P0441. A continuous purge condition with no purge commanded by the PCM should set a DTC
P1441. A fault in the EVAP Vacuum Switch circuit should set a DTC P1442.
IMAGE LEGEND
(1) EVAP Canister Purge Valve
(2) EVAP Vacuum Switch
