PleasureCraft Engine Group 5.0L, Руководство по диагностике

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4A - 4 Distributor Ignition 5.0/5.7L
MEFI 4 - PCM
Ignition Coil
M4093
Camshaft Position (CMP) Sensor and Reluctor
Wheel
The camshaft position (CMP) sensor works in conjunction
with a 1X reluctor wheel mounted inside the distributor
housing. The CMP is used to determine the top dead
center position of cylinder #1, and will synchronize with
the 4X CKP sensor signal for quicker starting. The CMP
signals are output as a digital waveform.
M4091
The DI ignition system may require the distributor to be
readjusted if it is moved for any reason. In the past, the
distributor would be rotated to adjust ignition timing. The
ignition timing on this engine is not adjustable. Moving
the distributor will NOT change ignition timing at all. The
ignition timing is determined and controlled by the ECM.
However, if the distributor is not positioned properly,
driveability problems will exist.
In order to properly set the distributor position, a scan tool
MUST be used. There is a parameter on the data stream
called ìCam Retard.î Cam retard must be set to 43-47
degrees, or driveability problems will exist.
The design construction of the ignition coil affects its output.
The DI system ignition coil was designed to produce greater
spark voltage, longer spark and operate at higher RPM.
The DI system coil has the secondary winding wrapped
around the primary winding, and the primary winding is
wrapped around the iron core. The coil is not oil fi lled, the
windings are covered in an epoxy compound for protection
against moisture and arc over.
There is an iron laminated square frame around the coil
windings. This is to increase magnetic fl ux path and store
energy to produce higher secondary spark voltage. The
coilís mounting bracket is attached to ground.
The coil generates a high secondary voltage (up to 35,000
volts) when the primary circuit is broken. A secondary
high tension wire connects from the top post of the coil to
the center post of the distributor cap. There is one 2-wire
connector on the coil that is used for battery voltage input
and the trigger signal from the IC module.