Spark plugs may not seem like a fascinating engine component, but they’re actually one of the most crucial. Without properly functioning spark plugs, your vehicle’s internal combustion engine can’t work correctly. Without the spark from your spark plug, your engine won’t start… which means you’re not going anywhere. They can also make a difference in how smooth your engine runs and how good your gas mileage is. Here’s everything you need to know about the unassuming spark plug.
What Do Spark Plugs Do?
Basically, spark plugs create the spark that starts your engine, but there’s more to it than that. They are an electronic device that plugs into the cylinder head on your vehicle’s engine. When you turn the key to start your car, the cylinder head is flooded with a combination of gasoline and air, which is igniting by the spark created by your spark plug. This mini-explosion drives the piston that connects to the crankshaft of the vehicle. That energy is ultimately transferred to the wheels of your car, making your vehicle move.
How to Tell if Spark Plugs Are Bad
Spark plugs require routine maintenance, just like fuel, air, and oil filters. In most cases, your spark plugs should be replaced once every 30,000 to 50,000 miles to keep your engine running at its best. A visual inspection of your plugs can tell you a lot. If you pull the plugs and the electrodes look thin, brittle, or worn, it’s time to replace them.
Some newer vehicles have been designed with advanced ignition systems that are supposed to eliminate the need to replace spark plugs, but if you are noticing any of the symptoms below, bad spark plugs could be the cause.
Symptoms of Bad Spark Plugs
Leaving your vehicle to operate without regular maintenance of spark plugs could result in some serious engine repairs.
Hard to Start
Vehicles with worn-out spark plugs are hard to start because they aren’t getting the spark needed to ignite the engine.
Slow Acceleration
If your car doesn’t gain speed as quickly as it used to, or it just runs a little sluggish, it could be time to replace your spark plugs.
Poor Fuel Economy
When spark plugs are functioning correctly, you’ll have excellent fuel economy. However, old plugs will have a gap between their electrodes, which is either too close or too far apart. This can lead to reduced fuel efficiency, and it is probably time for new spark plugs.
Misfiring Engine
If you notice that your engine is stumbling or stuttering, this is called misfiring. It can lead to a decrease in power and fuel efficiency. Misfiring can be caused by a sensor malfunction in newer cars, but a damaged spark plug tip or wire is a common cause in older vehicles.
Surging or Hesitating Engine
Sometimes, the engine of a car will hesitate during acceleration. Other times, it may surge forward and then slow down. This usually indicates that the vehicle is sucking in too much air, which is leading to delayed power delivery. When you notice both surging and hesitating, it could indicate worn-out spark plugs.
Idling Rough
Worn out spark plugs can cause your engine to vibrate and sound jittery of rough when idling.
The Best Spark Plugs
The best spark plugs for your vehicle will vary depending on its age. Here’s what you need to know to about choosing the best spark plugs for your car.
There are three common types of spark plugs:
- Copper: Copper plugs aren’t used much anymore. Although they are the cheapest, they don’t offer the lifespan or performance of other materials, and many modern engines can’t use them at all. However, for older vehicles, copper plugs may be the best choice.
- Platinum: Platinum spark plugs offer better fuel efficiency and performance than copper, but they’re not super expensive. For best performance, choose the ones with platinum in the cap and the electrode.
- Iridium: Iridium plugs are the most expensive, but they also last the longest and provide the best fuel efficiency and performance.
These are some of the best brands to consider:
- NGK Spark Plugs: NGK spark plugs are premium plugs that come with either platinum or iridium tips. This is the brand you want for high-performance vehicles.
- Champion Spark Plugs: Champion spark plugs are affordable because they still offer copper tips. They may not work with newer cars, but they could be the best choice for older models.
- Denso Spark Plugs: Denso plugs come with either twin platinum or iridium tips and a purified alumina powder insulator for a longer lifespan. They are a little on the pricy side, but they will improve performance and fuel efficiency, especially in newer cars.
- Autolite Spark Plugs: Autolite’s platinum spark plugs are an affordable and dependable plug. While they’re not designed for high-performance vehicles, they are excellent for everyday use.
Clearly, spark plugs are essential to a properly functioning engine. Thankfully, replacing your vehicle’s spark plugs is pretty affordable. If you are noticing any of the symptoms of worn-out spark plugs, contact your mechanic right away to see if it’s time to replace them.
