Diagnostic Aids
To locate an intermittent problem, use scan tool to monitor INTAKE PLENUM SWITCHOVER VALVE with ignition on, engine off. Wiggling wires while monitoring INTAKE PLENUM SWITCHOVER VALVE may locate area where a circuit fault may exist. These failures are only valid if intake plenum switchover solenoid is currently being commanded off.
Use scan tool to command INTAKE PLENUM SWITCHOVER SOLENOID on and off with ignition on, engine off. The solenoid should click when commanded on and off.