Description - Spark Plugs - Platinum
The 3.5L engines use platinum resistor spark plugs. They have resistance values of 6,000 to 20,000 ohms when checked with at least a 1000 volt tester. For spark plug identification and specifications, (Refer to SPARK PLUGS under SPECIFICATIONS.
Do not use an ohmmeter to check the resistance of the spark plugs. This will give an inaccurate reading.
The spark plugs are single platinum and have a recommended service life of 100,000 miles for normal driving conditions per schedule A. The spark plugs have a recommended service life of 75,000 miles for severe driving conditions.
A thin platinum pad is welded to the center electrode end as show in (see Fig 1 ). Extreme care must be used to prevent spark plug cross threading, mis-gaping and ceramic insulator damage during plug removal and installation.