Engine Emission Control
ENGINE EMISSION CONTROL4.6L Exhaust Gas Recirculation (EGR) System Module
CAUTION: Do not remove any part of the engine emission control system. Operating the engine without the engine emission control system will reduce fuel economy and engine ventilation. This will weaken engine performance and shorten engine life.
EGR System Components:
4.6L Exhaust Gas Recirculation (EGR) System Module:
The EGR system returns a portion of the exhaust gas to the intake manifold to reduce the combustion temperature. This results in lower nitrous oxide formation.
The PCM controls the EGR system module. When the EGR system module valve opens, exhaust gas flows to the intake manifold.
The EGR system module to exhaust manifold tube:
- connects the exhaust manifold to the EGR valve.
The EGR system module transducer:
- monitors the EGR system module flow rate through the EGR to exhaust manifold tube.
- sends an EGR system module flow rate signal to the PCM.
The EGR vacuum regulator solenoid uses input from the PCM to change the EGR system module operation. For further description and operation, refer to Computers and Control Systems.
5.4L EGR System
5.4L Exhaust Gas Recirculation (EGR) System:
The 5.4L engines are equipped with an EGR system. The function of the EGR system is to reduce the emission of nitrogen oxide (NOx).
The EGR system returns a portion of the exhaust gas to the intake manifold to reduce the combustion temperature. This reduces the oxides of nitrogen (NOx) in the exhaust emissions.
The PCM controls the EGR vacuum regulator solenoid. The EGR vacuum regulator solenoid controls the vacuum to the EGR valve. When the EGR valve opens, exhaust gas flows to the intake manifold. The differential pressure feedback EGR sensor measures the flow through the EGR valve to exhaust manifold tube and sends a signal to the PCM. A metering orifice in the EGR valve to exhaust manifold tube restricts the flow rate when the EGR valve is open.
For further description and operation, refer to Computers and Control Systems.
All Gasoline Engines
All gasoline engines are equipped with a positive crankcase ventilation (PCV) system. The function of the PCV system is to circulate blow-by gases from the engine crankcase to the engine intake.
The PCV system consists of:
- PCV valve
- PCV tube
The PCV valve:
- controls the amount of ventilating air and blow-by gases going to the intake manifold.
- prevents a backfire from reaching the crankcase.
For further description and operation, refer to Computers and Control Systems.