See Figure 1
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.
To check resistance, an ohmmeter should be used on each wire to test resistance between the end connectors. Remove and install/replace the wires in order, one-by-one.
Resistance on these wires should be 4,000-6,000 ohms per foot. To properly measure this, remove the wires from the plugs, coil, or the distributor cap. Do not pierce any ignition wire for any reason. Measure only from the two ends. Take the length and multiply it by 6,000 to achieve the maximum resistance allowable in each wire, resistance should not exceed this value. If resistance does exceed this value, replace the wire.
Whenever the high tension wires are removed from the plugs, coil, or distributor, silicone grease must be applied to the boot before reconnection. Coat the entire interior surface with Ford silicone grease D7AZ-19A331-A or its equivalent.
REMOVAL & INSTALLATION
See Figure 2
The 2.2L engine is the only engine covered in this guide that utilizes spark plug wires. The 2.3L and 2.4L engines have an integrated coil assembly that site over the spark plugs.
If all of the wires must be disconnected from the spark plugs or from the distributor at the same time, be sure to tag the wires to assure proper reconnection.
When installing a new set of spark plug wires, replace the wires one at a time so there will be no mix-up. Start by replacing the longest cable first. Install the boot firmly over the spark plug. Route the wire exactly the same as the original. Insert the nipple firmly onto the tower on the ignition coil, and attach the wire separators to secure the wires. Be sure to apply silicone dielectric compound to the spark plug wire boots and tower connectors prior to installation.