Spark plugs are very important to the structural integrity of an automobile, as they keep fuel economy up, misfires away and the vehicle in generally good working order. Changing the spark plugs in a Chevy Trailblazer is a very simple task which can be performed within a matter of minutes. All you need are the proper maintenance tools, some basic mechanical aptitude and knowledge about when the process should be done.

Replacing Spark Plugs

Your Trailblazer's spark plugs should be changed every 50,000 miles, although some copper plugs may last up to only about 30,000 miles. The only tools needed for this job are a 10mm ratchet to pop off your top assembly, which sits directly above the engine and holds your airbox, and a 5/8-inch ratchet with an extension to loosen and pull out the spark plugs. To remove a spark plug, pull out each ignition coil and put your ratchet down until it mates with the plug. Loosen the spark plug, and then pull it out of the casing of the engine. Then insert the new plug, making sure to put a bit of oil on its threads. Use the same type of oil that you put in your engine during an oil change. The oil helps prevent the plug's threads from stripping. This process should be done one spark plug at a time. Trying to do more than one could lead to confusion. You might accidentally remove a plug that you just put in, or you could put the wrong ignition coil into the wrong cylinder. Because cars have a certain firing order for each ignition coil, inserting a coil into the wrong spot will throw off the timing of the engine and make it run horribly. After all of the plugs have been replaced, make sure the ignition coils are back on and fit snugly onto their cylinders. Then start up the car to ensure that it is running well.

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YouTube: 06 TrailBlazer Spark Plug Removal