Charge Air Intake Valve
| ITEM | DESCRIPTION |
|---|---|
| 1 | Charge air recirculation solenoid |
| 2 | Charge air shut-off valve connecting rod |
| 3 | Vacuum connection |
| 4 | Vacuum actuator |
| 5 | Charge air intake valve air outlet to charge air cooler |
| 6 | Charge air intake valve body |
| 7 | Charge air recirculation solenoid valve body |
| 8 | Charge air inlet from fixed vane turbocharger |
| 9 | Charge air recirculation solenoid air outlet to Variable Geometry Turbocharger (VGT) clean air duct |
The charge air intake valve is attached to a bracket on the engine stiffening plate. The Powertrain Control Module (PCM) uses the valve to control the bi-turbocharger operation of the turbochargers.
The charge air intake valve consists of a recirculation solenoid and a shut-off valve that are connected together by four screws and a gasket. The recirculation solenoid controls the flow of air from the compressor of the secondary turbocharger to the clean air duct of the primary turbocharger. The shut-off valve controls the flow of air from the compressor of the secondary turbocharger to the charge air coolers.
The Engine Junction Box (EJB) provides power supply for the recirculation solenoid, the recirculation solenoid is operated by the PCM. When it is de-energized, the recirculation solenoid is closed.
If the charge air recirculation solenoid develops a fault it will default to the closed position. In this position an overspeed of the primary turbocharger will occur. This overspeed is sensed by the Manifold Absolute Pressure (MAP) sensor which detects the increase in pressure. The PCM registers the signals from the MAP sensor and operates the turbochargers in mono-turbo mode with restricted engine torque and Diagnostic Trouble Codes (DTC) recorded.
The shut-off valve is a flap valve operated by a vacuum actuator. The PCM operates the charge air solenoid to apply and release the vacuum in the actuator, which opens the valve when a vacuum is present. When the shut-off valve is open charge air from the secondary turbocharger flows through the valve to the charge air coolers.