The Viloran's maintenance manual recommends that owners replace the spark plugs every 40,000 kilometers. The spark plugs used in the Viloran are Bosch Platinum.
Viloran Spark Plug Replacement Guide
Since the process for replacing spark plugs in the L4 engine is similar to that of the V6 engine, and the structure of the four-cylinder engine is more streamlined, we will use the V6 engine as a demonstration.
1：Special Tools: If the owner is unsure about the special tools required, a repair toolbox can be purchased online.
2：Remove the Intake Pipe and Coolant Reservoir: (This step can be skipped for four-cylinder models.)
3：Remove the Ignition Coil: After removing these components, remember to take out the ignition coil. Then use a socket and wrench to remove the spark plugs. (Note: Ensure that the position of the socket and wrench is perpendicular to the spark plug during removal to avoid stripping the threads.)
4：Compare New and Old Spark Plugs: The differences are apparent. The old spark plugs have significant carbon buildup on the threads, but the ignition gap remains largely unchanged. Naturally aspirated engines can have the spark plugs cleaned and reused, while turbocharged engines require new spark plugs.
5：Installation: When installing, gently slide the spark plug down against the inner wall to avoid collisions that could affect the ignition gap of the spark plug.
