Safari Van AWD V6-4.3L VIN W (1996)
EGR Valve: Description and Operation
Exhaust Gas Recirculation (EGR) System Description
The linear Exhaust Gas Recirculation (EGR) valves look like a small motor.
The control module command exclusively operates the linear EGR valve (1). The control module monitors the following various engine parameters:
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The Throttle Position (TP) sensor.
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The Manifold Absolute Pressure (MAP).
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The Engine Coolant Temperature (ECT) sensor.
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The EGR Pintle position sensor.
Output messages are then sent to the EGR system indicating the proper amount of exhaust gas (2) recirculation [with intake air (3)] necessary in order to
lower the combustion temperatures. This electronic metering of exhaust gas is ten times faster than the vacuum-operated models as well as an improved
diagnostic capabilities.
Positioned at the top of the linear EGR assembly are 5 terminals.
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A is the pulse width modulated negative signal from the control module.
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B is the sensor ground.
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C is the sensor output.
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D is the +5 volts supply.
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E is the positive from ignition.
A 12 volt current which enters the valve through an electrical connector (terminal E) energizes the solenoid (bobbin and coil) assembly (3). The 12 volt
current then flows through the solenoid assembly to the control module and creates an electromagnetic field. This field causes the armature assembly
(4,6) to be pulled upward, lifting the pintle (5) a variable amount off the base.
The exhaust gas then flows from the exhaust manifold through the orifice into the intake manifold. The pintle position sensor (2,1-sensor cap) reads the
height of the pintle, and the control module closes the loop on a desired position versus the actual position read. This changes the pulse width modulated