Jeep 2007 Grand Cherokee - Manual (Page 367)

Spark Plugs
Spark plugs must fire properly to assure engine perfor-
mance and emission control. New spark plugs should be
installed at the specified mileage. The entire set should be
replaced if there is any malfunction due to a faulty spark
plug. Refer to the “Vehicle Emission Control Informa-
tion” label in the engine compartment for spark plug
information.
Spark Plug Wires
The spark plug wires should be kept clean and properly
connected. Terminals should be fully seated. Cracked,
damaged, or faulty wires should be replaced.
Engine Air Cleaner Filter
Under normal driving conditions, replace the air filter at
the intervals shown on “Maintenance Schedule A.” If,
however, you drive the vehicle frequently under dusty or
severe conditions, the filter element should be inspected
periodically and replaced if necessary at the intervals
shown on “Maintenance Schedule B.”
WARNING!
The air induction system (air cleaner, hoses, etc) can
provide a measure of protection in the case of engine
backfire. Do not remove the air induction system (air
cleaner, hoses, etc) unless such removal is necessary
for repair or maintenance. Make sure that no one is
near the engine compartment before starting the
vehicle with the air induction system (air cleaner,
hoses, etc) removed. Failure to do so can result in
serious personal injury.
MAINTAINING YOUR VEHICLE 367
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