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Ignition System Visual Inspection



***UPDATED BY TSB 288704 April 1987

The spark plug wires, distributor cap and rotor are subject to wear and electrical breakdown which will reduce their ability to deliver a precisely timed, strong spark. Many of these conditions are easily detected by a thorough visual inspection. Dirt and moisture on any of these component are also potential poor spark at the spark plugs.
1. Check the Distributor cap and rotor.
Remove the distributor cap and inspect the contacts of the cap and the rotor for corrosion, wear, pitting, or burning. If only light corrosion is present, contacts can be cleaned, but if any signs of pitting, wear or burning are observed, parts must be replaced.
2. Check for signs of cracking or carbon tracking. Cracks may be fine and difficult to see, so look carefully especially around the contacts. Carbon tracks are usually faint lines running between two or more contacts or to ground. Check for signs of carbon tracking under the radio suppression shield fitted over the cap. Remove the radio suppression shield from the cap and look for white spots or burn marks. Replace a distributor cap that shows any signs of cracks or carbon tracking.
3. Check the insulation of the spark plug wires for cracks or signs of abrasion. Bend the wires in several places to expose any small, or hidden cracks that may allow sparks to jump to ground. Replace any wires that are cracked, oil soaked, or brittle.
4. Check the spark plug connectors for signs of ignition sparks jumping to the head. Remove the spark plug connectors and look for white spots or burning on the connector and the head.
5. Check the coil for signs of cracking, burning, carbon tracking or leaking fluid. The coil tower, terminal 4, should be clean and dry. If necessary, remove the coil for cleaning and closer examination.