Spark plugs play a vital role in the internal combustion engine by igniting the gas in the cylinder head. The 2003 Toyota Camry is available in both four and six cylinder engines both of which use ignition coils for each cylinder. The recommended inspection and replacement interval for spark plugs is thirty thousand miles. Failure to replace spark plugs in a timely manner can result in a poor running engine and or decreased fuel mileage.
Label each wire connected to the ignition coil pack on top of each spark plug. On the four cylinder engine this will require four labels and six labels on the six cylinder engine.
Disconnect the wire on each coil pack by squeezing the connector and gently pulling while providing lateral motion.
Remove the 12 mm bolt that secures each coil pack to the engine. Use the 12 mm socket and ratchet to break the bolt loose and then remove the bolts by hand.
Remove each coil pack from the engine by pulling straight up and gently twisting the coil pack.
Remove the spark plugs from the engine by turning them counter clockwise using the spark plug socket, extension and ratchet.
Adjust the spark plug gap on the new spark plugs to .43 with the spark plug gap tool. The gap is correct when the tool will move between the spark plug and electrode with minimal resistance at the .43 setting.
Thread the new spark plugs into the engine by turning them clockwise using the spark plug socket and extension. Starting the spark plugs by will help mitigate the risk of cross threading into the engine.
Tighten each spark to thirteen foot pounds of torque using the spark plug socket, extension and torque wrench.
Replace a coil pack on each of the spark plugs by gently pressing down until the plug attachment seats. Turn the coil pack until the bolt hole on the coil pack aligns with bolt hole on the engine.
Insert into each coil pack and tighten down to 13 foot pounds of torque.