Chrysler 1998 Voyager Service Manual page 314

8D - 16 IGNITION SYSTEM
DESCRIPTION AND OPERATION
CAMSHAFT POSITION SENSOR . . . . . . . . . . . . 17
CRANKSHAFT POSITION SENSOR . . . . . . . . . . 16
FIRING ORDER—2.4L . . . . . . . . . . . . . . . . . . . . 16
INTAKE AIR TEMPERATURE SENSOR—2.4L . . . 17
REMOVAL AND INSTALLATION
CAMSHAFT POSITION SENSOR . . . . . . . . . . . . 19
CRANKSHAFT POSITION SENSOR . . . . . . . . . . 19
ENGINE COOLANT TEMPERATURE SENSOR—
2.4L . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
IGNITION COIL—2.4L . . . . . . . . . . . . . . . . . . . . . 18
INTAKE AIR TEMPERATURE SENSOR—2.4L . . . 21
DESCRIPTION AND OPERATION
FIRING ORDER—2.4L
FIRING ORDER—2.4L
CRANKSHAFT POSITION SENSOR
The PCM determines what cylinder to fire from the
crankshaft position sensor input and the camshaft
position sensor input. The second crankshaft counter-
weight has machined into it two sets of four timing
reference notches and a 60 degree signature notch
(Fig. 1). From the crankshaft position sensor input
the PCM determines engine speed and crankshaft
angle (position).
2.4L ENGINE
INDEX
page
KNOCK SENSOR—2.4L . . . . . . . . . . . . . . . . . . . 21
MANIFOLD ABSOLUTE PRESSURE (MAP)
SENSOR—2.4/3.3/3.8L . . . . . . . . . . . . . . . . . . 20
SPARK PLUG CABLE SERVICE—2.4L . . . . . . . . 18
SPARK PLUG SERVICE . . . . . . . . . . . . . . . . . . . 18
THROTTLE POSITION SENSOR . . . . . . . . . . . . 20
SPECIFICATIONS
IGNITION COIL . . . . . . . . . . . . . . . . . . . . . . . . . 22
SPARK PLUG CABLE RESISTANCE—2.4L . . . . . 22
SPARK PLUG . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
TORQUE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
The notches generate pulses from high to low in
the crankshaft position sensor output voltage. When
a metal portion of the counterweight aligns with the
crankshaft position sensor, the sensor output voltage
goes low (less than 0.3 volts). When a notch aligns
with the sensor, voltage switches high (5.0 volts). As
a group of notches pass under the sensor, the output
voltage switches from low (metal) to high (notch)
then back to low.
If available, an oscilloscope can display the square
wave patterns of each voltage pulse. From the width
of the output voltage pulses, the PCM calculates
engine speed. The width of the pulses represent the
amount of time the output voltage stays high before
switching back to low. The period of time the sensor
output voltage stays high before switching back to
low is referred to as pulse width. The faster the
Fig. 1 Timing Reference Notches
NS
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