Spark Plugs

WARNING: This page is about a different car, the 2003 Jeep Liberty. However, it is still accessible from the selected car via links, so may be relevant.

Resistor type spark plugs are used. Spark plug resistance values range from 6000 to 20,000 ohms when checked with at least a 1000-volt spark plug tester. Do not use an ohmmeter to check the resistance values of the spark plugs. Inaccurate readings will result. To prevent possible pre-ignition and/or mechanical engine damage, the correct type/heat range/number spark plug must be used. Always use the recommended torque when tightening spark plugs. See SPARK PLUGS in SERVICE & ADJUSTMENT SPECIFICATIONS - LIBERTY article. This is especially true when plugs are equipped with tapered seats. Incorrect torque can distort the spark plug and change plug gap. It can also pull the plug threads and do possible damage to both the spark plug and the cylinder head. When removing the spark plugs, examine them for burned electrodes and fouled, cracked or broken porcelain insulators. Keep plugs arranged in the order in which they were removed from the engine.

A single plug displaying an abnormal condition indicates that a problem exists in the corresponding cylinder. Replace spark plugs at the recommended service intervals. See SPARK PLUGS in SERVICE & ADJUSTMENT SPECIFICATIONS - LIBERTY article. Spark plugs that have low mileage may be cleaned and reused if not otherwise defective, carbon or oil fouled.

CAUTION: Never use a motorized wire wheel brush to clean the spark plugs. Metallic deposits will remain on the spark plug insulator and will cause plug misfire.