EXHAUST GAS RECIRCULATION
TABLE OF CONTENTS
page
page
VALVE-EGR
DESCRIPTION
. . . . . . . . . . . . . . . . . . . . . . . . . 26
OPERATION
. . . . . . . . . . . . . . . . . . . . . . . . . . . 26
REMOVAL
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
INSTALLATION
. . . . . . . . . . . . . . . . . . . . . . . . . 29
VALVE-EGR
DESCRIPTION
4.7L Engine
The electronic EGR valve and solenoid assembly (3)
is attached to the rear of the left cylinder head. An
exhaust gas routing tube (1) connects the EGR valve
to the intake manifold.
OPERATION
Exhaust gas recirculation flow is determined by the Powertrain Control Module (PCM) and is controlled by an elec-
tronic EGR valve assembly. For a given set of conditions, the PCM knows the ideal exhaust gas recirculation flow
to optimize NOx and fuel economy as a function of the pintle position. Pintle position is obtained from the position
sensor. The PCM adjusts the duty cycle of 128 Hz power supplied to the solenoid coil to obtain the correct position.
The electronic EGR valve assembly consists of a pintle, valve seat, and housing which contains and regulates
exhaust gas flow. An armature, return spring, and solenoid coil provide the operating force to regulate exhaust gas
flow by changing the pintle position. The solenoid coil assembly is wired in parallel with a diode that connects two
internal connectors.
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EXHAUST GAS RECIRCULATION
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