Inspecting and Exchanging Plugs / Sevice Life

Guideline for replacing plugs

When the tip of the center electrode becomes worn to a rounded shape, this interferes with sparking and may prevent stable ignition of the fuel mixture. Because this can lead to reduced horsepower and poor mileage and can have a negative effect on engine life, replacing the spark plug is recommended.

Recommended timing for replacing normal spark plugs

4-wheel passenger vehicles: 15,000 to 20,000 km
Light automobiles: 7,000 to 10,000 km
Motorcycles: 3,000 to 5,000 km

We recommend that you check and replace your spark plugs as necessary for favorable driving.

Time for replacement

These kinds of problems can occur!

Poor mileage
Poor engine starting
Reduced horsepower
Unstable idling

New plug

Effect following spark plug replacement