Service manual

G424F(FE) Service Manual Chapter 4. Engine Electrical System 104
Spark Plug Wire Inspection
Sparking plug wire integrity is vital for proper engine
operation. A Thorough inspection will be necessary
to accurately identify conditions that may affect
engine operation. Inspect for the following condition:
1. Correct routing of the spark plug wires. Incorrect
routing may cause cross-firing
2. Any signs of cracks or splits in the wires
3. Inspect each boot for the following conditions:
• Tearing
• Piercing
• Arcing
• Carbon tracking
• Corroded terminal
If corrosion, carbon tracking, or arcing is indicated
on a spark plug boot or on a terminal, replace the
wire and the component connected to the wire.
Spark Plug Wire Replacement
Removal
Remove or disconnect
1. Disconnect the spark plug wire at each spark plug.
See Figure 81
a. Twist the boots 1/2 turn before removing the
boots
b. Pull only on the boot or use a tool designed for
this purpose in order to remove the wire from
each spark plug.
2. Disconnect the spark plug wire from the coil pack.
a. Twist each spark plug boot 1/2 turn.
b. Pull only on the boot or use a tool designed for
this purpose in order to remove the wires from
the coil pack.
Installation
Install or connect
Note: If the boot-to-wire movement has occurred,
the boot will give a false visual impression of being
fully seated. Ensure that the boots have been
properly assembled by pushing sideway on the
installed boots. Failure to properly seat the terminal
onto the spark plug will lead to wire core erosion an
result in an engine misfire or crossfire condition and
possible internal damage to the engine.
1. Install the spark plug wires at the coil pack. You
should feel the terminal snap onto the coil.
2. Install the spark plug wire to each spark plug. You
should feel the terminal snap onto the spark plug.
See Figure 81.
3. Inspect the wires for proper installation:
a. Push sideways on each boot in order to inspect
the seating.
b. Reinstall any loose boot. You should feel the
terminal snap onto the spark plug or coil when
installing the spark plug wire. Inspect and
replace component that is damaged
c. Wire routing must be kept intact during service
and followed exactly when wires have been
disconnected or when replacement of the wires
is necessary. Failure to route the wires
properly can lead to radio ignition noise and
cross firing of the plugs or shorting of the leads
to the ground.
d. Any time the spark plug wires or boots are
installed on the spark plug, new dielectric
grease needs to be applied inside the boot.