Auto Repair Encyclopedia
Spark Plugs Replacement
Sometimes referred to as Spark Plugs, Spark Plug, Replace Spark Plugs, Replace Spark Plug, Spark Plug Replace, Spark Plugs Replace, Plugs, Replace Plugs
Spark plugs are part of the vehicle's ignition system; they contain two electrodes across which electricity jumps to produce a spark that ignites the gas in the engine. The energy caused by the combustion is converted into energy used to power the wheels.
Spark plugs generally come one per engine cylinder and are replaced during the manufacturer recommended maintenance interval, which has traditionally been every 30,000 miles, but now many vehicles can go 100,000 miles before the recommended replacement interval.
Worn spark plugs can cause poor fuel economy, poor drivability, difficulty starting the engine, and high pollution emissions.
To replace the spark plugs, the spark plug wire or ignition coil is removed from each spark plug. The spark plug is unscrewed from the engine, and a new spark plug is installed.
Mechanics' Corner: More Technical Detail
Access to the spark plugs can be very limited on modern vehicles. Some require the removal of major components—the intake manifold, pipes, and hoses—while others can be straightforward.
About this Repair: Spark Plug Replacement
Recommendations
To prevent ignition misfires and Check Engine Light problems, we recommend using only high quality spark plugs, and preferably spark plugs from the OEM.
Spark Plugs have different ratings and it's important that the correct type are used.
Spark Plug terminals wear down over time and can lead to engine misfires. A the very minimum they need to be replaced at the mileage specified by the vehicle manufacturer.
Why this happens
Failing spark plugs can cause the engine to run rough and misfire, causing the Check Engine Light to come on. Continuing to drive under these conditions can damage the catalytic converter.
