What do I need to Know About Spark Plugs?

February 26th, 2015 by



What Do You Need to Know About Spark Plugs

Everyone’s heard of spark plugs, they have to do with your engine but beyond that you may not know much. Here are the basics, spark plugs are what get everything started in an internal combustion engine, they shoot the spark that ignites the fuel and air and puts the engines pistons into motion. The spark plugs continue to cause combustion in the engine throughout operation of your vehicle, and promote smooth operation of the engine by causing combustion in all of the cylinders of your engine.

Spark plugs are exposed to harsh conditions in your engine, extremely high temperatures and pressure are common, but are manufactured to be durable. Like really durable, that’s the reason spark plugs are easy to overlook as far as automotive maintenance, they’re built to last for 100,000 miles. This durability is made even more impressive by the conditions they’re exposed to, but those conditions are hard on the spark plugs and can cause them to fail prematurely.

Potential Issues Caused by Spark Plug Failure

Spark plug failure can lead to issues with the engines performance or costly repairs, but all of this is easily preventable. As previously started, they are made to last 100,000 miles. Given that spark plugs aren’t expensive to replace, it’s worthwhile to think about replacing them before they are 100% used up. If a plug fails when it has 95,000 miles on it and cracks into the engine cylinder, it could lead to costly repairs and isn’t the fault of the spark plug that had worked for 95,000 miles.  80,000 miles is a good spot to think about replacing spark plugs to avoid any issues from the aging component. Any component can have issues though, and failing spark plugs can be related to any of the following issues:

  • Your Engine is suffering from a rough idle
    • At idle, your engine should be at 1000rpm and produce a smooth, uniform sound. If at idle your rpms are fluctuating, your engine is producing a rough noise, or producing more vibration than normal, your spark plugs may be to blame.
  • Your vehicle is having issues starting
    • Trouble starting your car might not be due to the battery as most people assume, spark plug failure could also do it. If they aren’t producing sparks, there’s nothing to get the engine going, and they could be causing battery issues.
  • Has you engine misfired?
    • If not all of the cylinders of your engine are running properly, it can cause your engine to temporarily  cut off for a moment and then return to normal function, which results in a misfire. Obviously this means the engine isn’t functioning properly, and it could be due to the spark plugs.
  • Is your engine fluctuating in throttle and rpm?
    • If your engine is surging, or phasing out then jerking forward or the reverse, it’s caused by your engine working inefficiently and it could be due to issues with your spark plugs.
  • Higher than normal fuel consumption
    • Along with other inefficiencies, spark plug failure can lead to incomplete combustion in a cylinder which can cause fuel economy to decrease by up to 30%.
  • Is your vehicle slower than it used to be?
    • Any sort of sluggishness from your vehicle or a lack or response from the throttle could be attributed  to a poorly performing spark plug causing engine inefficiency.

Spark plugs are not a major service and won’t be a big hit to your wallet, unless you wait until one of them completely fails and potentially falls into the cylinder. You can also replace the spark plugs yourself as you may already know or with a little bit of research, but as you can see from the points above, testing and replacing spark plugs can alleviate many issues with the performance of your vehicle’s engine.