* Condition of the wires: Visually inspect the wires regularly. Look for:
* Cracks or brittleness: Wires that are cracked or brittle are likely failing and need replacement.
* Burning or melting: This indicates excessive heat and potential damage to the insulation.
* Loose connections: Check the connections at both the spark plug and distributor (if applicable) for tightness and corrosion.
* Worn insulation: If the insulation is worn thin or damaged, it can cause misfires and electrical shorts.
* Engine performance: If you notice any of these symptoms, it could indicate a problem with the spark plug wires:
* Misfires: Rough running, hesitation, or sputtering.
* Hard starting: Difficulty starting the engine.
* Poor fuel economy: Lower than expected gas mileage.
* Check engine light: A check engine light often illuminates when misfires are detected.
* Mileage: While there's no strict mileage recommendation, many mechanics suggest replacing spark plug wires every 60,000-100,000 miles as a preventative measure. However, given the age of the vehicle (25+ years), even if they haven't reached that mileage, proactive replacement might be wise due to age-related deterioration of the rubber and insulation.
In short: Regular visual inspection is key. If you see any signs of wear or damage, or experience engine performance issues, replace them immediately. If you're unsure, err on the side of caution and replace them if they are approaching 100,000 miles or show any signs of degradation. It's a relatively inexpensive preventative maintenance item that can prevent more costly repairs down the road.
