Symptoms Of Bad Spark Plugs & How To Change Them

You may not know it, but dealing with spark plug issues is well within your abilities. The following guide will help you diagnose your spark plugs and change them if needed.

Symptoms of Faulty Spark Plugs

Your spark plugs act as lightning bolts for your vehicle. This spark is essential to get your engine running correctly.  The following list of symptoms may be telling you that you have bad spark plugs:

  • Rough idle is one sign to look for. Bad spark plugs will not give your vehicle enough power to idle smoothly. You will hear jittery sounds from your engine or feel uncommon vibrations.
  • Bad spark plugs can also give you startup problems. Spark plugs, again, are responsible for proper combustion. So your car may fail to start without spark plug ignition. 
  • Misfires and slow acceleration may also be telling you that you have bad spark plugs. Spark plugs are responsible for your vehicle's ability to respond to your power and speed needs. 
  • Your fuel economy will suffer as you find the need to press on your gas pedal more than usual to get your car moving. 

Changing your spark plugs should fix the aforementioned issues. But remember that some of the symptoms mentioned can also be associated with other problems, like bad spark plug wires. A full tune up may be necessary so talk to your tune-up specialist if the problem continues. 

Prep to Change Your Spark Plugs

You will need the following:

  • Your owner's manual
  • A ratchet socket drive wrench
  • An extension bar
  • Spark plug socket, but chances are that you already have that in your socket set
  • Spark gap gauge
  • New spark plugs

You can get the aforementioned at your local auto parts store or online. Be sure that you get the parts that fit your particular car. You can get this information from your owners manual, your tune-up specialist or auto parts specialist. 

Change Your Own Spark Plugs

To change your spark plugs, just follow the steps below:

  1. Be sure to let your car cool down before you work on it.
  2. Locate your spark plugs. They are usually sitting on top of your engine. 
  3. Carefully remove the wire plug to gain access to your spark plugs.
  4. Label each wire plug so you know how to connect it later.
  5. Fit your socket wrench with your extension, and use the ratchet to reach and release your first spark plug. 
  6. Use your gap to see if the spark plug contacts have burned out. The gap should be between .028 to .060. Replace if they are not in that range. You will need to talk to your tune-up specialist should your spark plugs be in perfect condition. The problem may need a closer look.
  7. Now just simply use your extension socket wrench and ratchet to install your new spark plugs. Reconnect the wire plugs in the order that they were in, and you are done. 

As you can see, changing your own spark plugs is not too hard and should save you some money.