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Engine Tune-up

Step 7 - Remove Spark Plugs

Socket Wrench Removing Spark Plug

Next, remove debris from the spark plug hole, (canned air works best) then use a socket wrench and spark plug socket to loosen and remove spark plug (counter clockwise). Inspect spark plug for damage.

Step 8 - Replace Spark Plug

Measuring Spark Plug Gap

Remove the spark plug from the box or container and inspect the new plug for damage that could have occurred in shipping. A spark plug has a porcelain isolator that is fragile and can crack easily. Next inspect the spark plug gap using a spark plug gap checker. The "air gap" should be measured as per manufacturer specifications. Most plug gaps are between .035 and .045 thousands of an inch. This gap is important because it determines the amount of resistance used to "time" the system. An incorrect spark plug gap will result in poor running, low power, poor mileage and a check engine light notice. Reinstall the spark plug and install the new spark plug wire. Most of the time a spark plug will come "pre-set" and ready to install. Continue the process until all spark plugs and spark plug wires have been replaced. Be sure to use OE (original equipment) parts for your car to insure the proper performance from your vehicle. This tutorial has outlined a tune up on a gasoline power engine, four cylinder. Most gasoline powered cars are similar.

Required Tune Up Parts

Before starting determine which tune up parts are needed. Inspect the particular system on your car or truck then purchase the appropriate parts to complete the job.

Spark Plugs - A spark plug will last between 20,000 and 60,000 miles depending on the style of spark plug that is required by your specific vehicle. The spark plug is the firing point in which the electricity is passed through a gap to ignite the fuel/air mixture inside the engine (combustion chamber).

Spark Plug Wires - Spark plug wires need to be changed every time a tune up is performed. With today's ignition systems, the running voltage and amperage is higher than ever; even more reason to service your spark plugs wires before they burn out and cause a misfire.

Ignition Rotor - An ignition rotor is used to relay the electrical spark from the ignition coil to the terminals on the distributor cap and then onto the sparkplug wires and eventually to the spark plugs. Some cars and trucks do not use an ignition rotor so inspect your vehicle before you start.

Fuel Filter - Fuel filters will last up to 25,000 miles or more depending on the type of driving you do. If you live in a dusty area like the desert or if there is extreme moister in your area, you can expect to change your fuel, oil and air filter more often. Make sure to replace your fuel filter at regular intervals to insure the safety of your vehicles fuel injection system.

Distributor Cap - A distributor cap is the component that allows the ignition spark from the ignition coil and separates it into the individual spark plugs as it rotates inside the ignition distributor. Some cars and trucks do not use an ignition rotor so inspect your vehicle before you start.

Air Filter - Air filters will last up to 3,000 miles or more depending on the type of driving you do. If you live in a dusty area like the desert or if there is extreme moister you can expect to change your oil and oil filter's more often. Make sure to inspect your oil level at regular intervals to insure the safety of the internal parts system of your vehicle. To inspect or change your air filter follow the instructions above.

Oil Filter - Oil filters will last up to 3,000 miles or more depending on the type of driving you do. Different oil types, like synthetic, give you more mileage between services. If you don't know when the last oil change was on your vehicle and would like to determine where you stand, remove the oil level inductor and check the clarity of the oil. If it is light colored like tea, you are ok. If it is dark like Cola, it is time for service.

If further assistance is needed, our certified car repair technicians are ready to answer your car questions.

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