ALT-2 How to Replace Spark Plugs
Before you open your hood and go into shock or think your vehicle is missing 3 or 4 spark plugs, Get out from underneath that shade tree and come to the understanding that it's no longer an easy task to remove and replace spark plugs. Today's complex designs leave little room for the do it yourself mechanic and little room for error. Before you tackle this project keep a few things in mind. This may turn into a job your just not equipped to handle.
First ask yourself the following questions, how long have these spark plugs been in the cylinder head? are they going to come out without damaging the aluminum head? do I have the proper tools for the task at hand? I love this question, where is the back spark plugs and how do I get to them? If you find yourself asking these questions you may be better off taking your vehicle into a repair facility.
But if your bound and determined to do it yourself here are some helpful tips on changing spark plugs. Never attempt to remove your spark plugs from a hot engine. Be patient and allow the engine time to cool down. This will not only save you a lot of grief but it will also save you a lot of money by preventing the spark plug from breaking off in the head or worse, damaging the cylinder head.
Never just grab the spark plug wire and pull or yank on it, firmly grasp the boot and twist back and forth to loosen the boot from the plug. If you can purchase a pair of spark plug boot pullers, this will make the job a whole lot easier.
Once you have the plug wire off, label which one you removed and from what cylinder. You can either use tape or a marker and label 1, 2, 3, 4 and so on so you do not mix up the firing order. Or you can simply replace the spark plugs one at a time.
Spray some penetrating oil on the spark plug to aid in the easy removal. Use the appropriate size spark plug socket and you may also depending on the vehicle need an extension and a swivel. If you use a swivel use only an impact swivel, it will not bind up on you when you are ratcheting out the plug. Never force the spark plug out, take your time. Here is an old shop secret, once the spark plug is loose, find an old spark plug boot, place it on the tip of an extension or screw driver and attach it to the tip of the spark plug to remove the plug easily. This also aids in the installation of the new plug.
Next and very important be sure to properly gap your new spark plugs. Never trust the auto parts guy to give you the proper gap. Double check by either purchasing a repair manual for your vehicle, or here is another trade secret look at your catalyst label under the hood. This can be found in various places, on the shock or strut tower, or on the fan shroud. Look for the white label, this will give your the proper gap and other manufacture specifications.
Replace the spark plug by turning slowly until snug, then give it just one more turn or until the spark plug is secure in the head. Now replace the boot and wire.
Caution, Some vehicles require removing a cover to obtain access to the plugs. For instance on a four cylinder grand am 4.2 liter quad four you have to remove the coil cover to gain access. To do this remove the electrical connector at the cover. This is the connector for the module. Next remove the coil cover bolts. Be careful not to remove the wrong bolts like the head bolts. I have seen this done before, if in doubt, ship it out. Next gently lift the cover up and off of the isolators or coil boots. look down the plugs are deep in the cylinders. Always replace the coil boots when you change the plugs.
To obtain access to the back spark plugs on some vehicles you will be required to remove the motor mounts or dog bones as they are commonly referred to. You will need a special tool to hook up to roll the engine forward enough to get to the back plugs.
Some vehicles require the removal of the intake manifold.
Vans and custom vans you will want to remove the engine cover or dog house as it is called by many a technician.
Some spark plugs today are hidden under individual coils. Care and caution must be used and their is no simple explanation to give you on removal.
A lot to take into consideration when thinking its easy or how easy is it to remove spark plugs.
If your spark plugs are easy to access then you should be alright replacing them on your own.
If not and you have doubt, take your vehicle into a certified repair facility.
