Spark Plug: Description and Operation

Fig 2 Setting Plug Electrode Gap -- Typical:

SPARK PLUGS
The Viper 8.0L V-1O engine uses resistor spark plugs. They have resistance values of 6,000 to 20,000 ohms when checked with at least a 1,000 volt tester.

Remove the spark plugs and 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. An isolated plug displaying an abnormal condition indicates that a problem exists in the corresponding cylinder. Replace spark plugs at the intervals recommended.

Spark plugs that have low mileage may be cleaned and reused if not otherwise defective. Refer to Testing and Inspection/Spark Plug Conditions. After cleaning, file the center electrode flat with a small flat file or jewelers file. Adjust the gap between the electrodes (Fig. 2) to the dimensions specified.

Always tighten spark plugs to the specified torque. Over tightening can cause distortion resulting in a change in the spark plug gap. Tighten spark plugs to 28 Nm (20 ft. lbs.) torque.