SYSTEMS
SPARK PLUGS
INSPECTING YOUR SPARK PLUGS
GAPPING YOUR SPARK PLUGSReplacing Your Spark Plugs
*MEDIUM*
You should replace your spark plugs every 30,000 miles unless they have a longer guaranteed useful life. Aside from collecting deposits, the electrodes can wear away from continuous sparking. The gap actually widens with spark plug use and causes ignition problems. Installation of new spark plugs can boost gas mileage by about 3%.
To replace spark plugs, follow the removal and insertion procedure outlined under Inspecting Your Spark Plugs, but use a new spark plug in place of the original. Be sure to adjust the gap on your new spark plugs before using them.
When selecting replacement plugs, follow your vehicle manufacturer's recommendations exactly with regard to heat range and gapping. It is permissible to select alternative plugs for certain situations. For example, if your vehicle will be predominantly driven at high speed, a colder plug will help prevent the spark plug tip from overheating and causing preignition. On the other hand, if the engine is worn and burns oil, a hotter plug will reduce spark plug fouling by burning off oil deposits. Consult a professional automotive technician when using spark plugs other than those recommended by the vehicle manufacturer.
SYSTEMS SPARK PLUGS INSPECTING YOUR SPARK PLUGS GAPPING YOUR SPARK PLUGS