5.0/5.7L Distributor Ignition 4A - 5
MEFI 4 - PCM
Noteworthy Ignition Information
There are important considerations to point out when
servicing the ignition system. The following noteworthy
information will list some of these to help the technician in
servicing the ignition system.
• The ignition coils secondary voltage output
capabilities are very high - more than 40,000
volts. Avoid body contact with ignition high voltage
secondary components when the engine is running
or personal injury may result.
• The 4X crankshaft position (CKP) sensor is the
most critical part of the ignition system. If the sensor
is damaged so that the pulses are not generated,
the engine does not start.
• The CKP sensor clearance is very important. If the
interrupter ring is bent or damaged in any way,
the CKP sensor may be destroyed. Extreme care
must be exercised during removal and installation
procedures.
• The ignition timing is not adjustable. Moving the
distributor changes the “Cam Retard.” Cam Retard
MUST be set at 43-47 degrees, or a driveability
problem will exist.
• Be careful not to damage the secondary ignition
wires or boots when servicing the ignition system.
Rotate each boot in order to dislodge the boot from
the plug or coil/cap tower before pulling the boot
from the spark plug or the coil/cap tower.
Engine Control Module (ECM)
The ECM is responsible for maintaining proper spark and
fuel injection timing for all driving conditions. To provide
optimum driveability and emissions, the ECM monitors
input signals from the additional following components in
calculating ignition control (IC) spark timing:
• The engine coolant temperature (ECT) sensor
• The intake air temperature (IAT) sensor
• The throttle position (TP) sensor
• The manifold absolute pressure (MAP) sensor
To Next Page
Loading...
Need help?
General
