### Spark Plug Wires

#### TESTING

Fig. 1: Checking individual plug wire resistance with a digital ohmmeter

At every tune-up/inspection, visually check the spark plug cables for burns cuts, or breaks in the insulation. Check the boots and the nipples on the distributor cap and/or coil. Replace any damaged wiring.

Every 50,000 miles (80,000 Km) or 60 months, the resistance of the wires should be checked with an ohmmeter. Wires with excessive resistance will cause misfiring, and may make the engine difficult to start in damp weather.

Using an ohmmeter, measure the resistance of the plug wire. Place the negative terminal of the ohmmeter on the cap end of the wire and the positive terminal end on the plug end. Maximum resistance should be 25 kilometer per wire. If the resistance is not within specifications, it is advisable to replace all the plug wires as a set.