How Often Should the Highlander's Spark Plugs Be Replaced?
3 Answers
Under normal circumstances, the spark plugs of a Toyota Highlander have a service life of no more than 30,000 kilometers. Additionally, you can determine whether early replacement is necessary based on the symptoms of spark plug failure. Damaged spark plugs may exhibit the following conditions: difficulty starting, reduced power, excessive exhaust emissions, and increased fuel consumption. Steps for replacing spark plugs: Open the hood, lift the plastic engine cover, remove the high-voltage distributor wires, and mark each cylinder's position to avoid confusion. Use a spark plug socket to remove the spark plugs one by one. While removing them, check for external debris such as leaves or dust and ensure everything is cleaned thoroughly. Place the new spark plugs into the spark plug holes, hand-tighten them a few turns, and then use the socket to tighten them further. Reinstall the removed high-voltage distributor wires in the correct firing order, then secure the cover back in place.
My Highlander is a model from a few years ago. According to the manual's recommendation, spark plugs should generally be replaced every 80,000 to 100,000 kilometers, but this is not absolute. My driving habits involve frequent starts and stops in the city, which can cause the spark plugs to wear out faster. I estimate they should be checked around 70,000 kilometers. Continuing to use old spark plugs can lead to engine shaking, delayed ignition, potentially increasing fuel consumption by over 10%, and slower acceleration. Regular replacement helps keep the engine running smoothly and avoids higher repair costs. I recommend getting a professional shop or 4S store to test the spark plug gap—it's worry-free and safe, especially important for those who drive long distances.
I started maintaining my Highlander by myself a few years ago. The replacement interval for spark plugs is approximately 100,000 kilometers. Manual replacement is quite easy—just get the matching iridium spark plugs and wrench tools, then unscrew the old spark plugs step by step. Remember not to break the ceramic shell. Delaying replacement can lead to increased carbon deposits, causing ignition failure, louder engine noise, reduced driving pleasure, and potentially shortening the lifespan of the ignition coil. After replacing them myself, the car responds much faster, saving a lot on fuel costs. Regularly cleaning the air filter can also extend the life of the spark plugs, making the Highlander more durable.
