How to Replace A Spark Plug

a car with open hood showing the engine

A spark plug is small device that is responsible for delivering electric current from your ignition system to the combustion chamber of a spark-ignition engine to startup the compressed fuel/air mixture by a “spark”, while subduing combustion pressure in your engine.

A spark plug has two main functions: to ignite or startup air/fuel mixture and to get rid of heat in the combustion chamber

A lot of us may have already know what a spark plug does without further explanations. It is just a matter of  will you be able to replace it on your own or will you be bringing it to your trusted mechanic for replacing?

If you wanted to DIY and replace it yourself, we have enumerated the steps on how you can do it successfully.

  1. Turn off the engine and wait for it to cool.
  1. Once it cool down, pull the hood release lever that is located under the dashboard.
  1. Next, go at the front of your car, reach under the hood and squeeze the latch open. You will see located in a row along the engine and attached to the thick wire are the plugs that are screwed directly into the engine, one per cylinder. Look for the indentation along the engine’s top. Each wire connects a plug to a specific wire one by one, it is recommended that you change the plugs one by one.
  1. Pull the L-shaped rubber boot that is attached to the plug wire to uncover the spark plug’s terminal. Make sure you blow out any debris around the spark plugs because the last thing that you want is getting foreign particles from falling inside your engine which may cause untimely damage.
  1. Now, once you’ve done that, loosen up the sparkplug with your tool and pull it off the engine block. If you see that the sparkplug tip is a colour of grayish or tan, this indicates that you still have a healthy spark plug and needs no replacing, but is you see heavy deposits or a blackened appearance, a need for replacement is necessary as this indicates an engine problem. Any signs of physical damage also needs replacing it.`
  1. Next, insert the spark plug gapping tool in the gap between central electrode and the metal side electrode of the plug’s tip. Look at the tool’s ruled edge to read the measurement. If the gap is too large, tap down on one side of the electrode with the tool to widen it. If it is too small, bend the side electrode up slightly with the gapping tool. Repeat the procedure for each plugs. Refer to your car’s repair manual to check on the gap size.
  1. Tighten the new spark plugs, using your hand, into place and complete the process using the socket and ratchet wrench. Make sure to screw the sparkplugs straight and just right. Do not under tighten or over tighten it. Also remember, a skewed spark plugs can cross threads and you will have a problem.
  1. Once you’re done replacing the spark plugs, start the engine, if the sound is rough, you may have to repeat the process over.

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