Vehicle Not Starting? Check Your Spark Plugs

It's roughly the size of your index finger, and weighs 2-3 ounces at most. But without it, can make a 16-feet, 7,000-lb SUV move as dead as that chunky paper weight in your office in no time.

Still, many forget spark plugs exist. Perhaps it's because it works tirelessly--yet quietly--behind the scenes. Too bad though; because if your car's engine could talk, it would probably say it would be worthless without the humble, self-effacing spark plug to do its job.

What are spark plugs?

Spark plugs--or flame igniters--are responsible for igniting the fuel that your internal-combustion engine needs to run your vehicle. They can fire 400 times per minute per cylinder, and in each time, create a small "spark" to turn fuel into energy. And that's the energy your engine uses to power a vehicle.

Since they're the hardest-working car part, it won't come as a surprise that they wear out over time and should be replaced regularly. Otherwise, they can cause your engine to misfire, and make your car run--if it does run--like it's in dire need of a blood transfusion.

So how do you know if your spark plugs need to be replaced ASAP? Here are some signs you should watch out for:

High fuel consumption

Worn-out spark plugs need more fuel to work than what's needed. This leads to inefficient use of fuel, leading to poor fuel economy.

Difficulty starting the vehicle

Many people assume that their batteries are dead when their vehicles aren't starting. And while it may be the case, there's also a possibility that the spark plugs are draining out your battery.

Engine misfiring

Similarly, if your car did manage to start itself, but feels jerky, erratic, or surging, then your spark plugs might be malfunctioning. Once they do, then your cylinders won't also fire properly, creating those strange movements.

Sluggish acceleration

Do you feel like your vehicle is dragging itself while moving? Or  does it feel like it doesn't instantly accelerate as soon as you press down on the gas pedal? Then you might be experiencing sluggish acceleration. And while there are many reasons why your car isn't as fast as it once was, a worn-out or defective spark plug may be one of them.

Knocking noises

Don't get scared when you hear pinging or rattling noises coming from your engine. It might just be your spark plugs firing at the wrong time, making your pistons and combustion work improperly. Hence, creating those strange, knocking sounds.

Then again, it might just be your neighbor's cat or mouse rummaging for food somewhere. When in doubt, a flashlight can do wonders to satisfy one's curiosity.

Final Word

Ideally, it's best to change your spark plugs every 4,800 km--or before they get worn out. Do take this with a grain of salt though, since we would still recommend you check your car's manual to really know the exact time to replace them.

Still, there are some cases you don't even need to wait before they reach shelf life. High-performance spark plugs, iridium- or platinum- made ones, engine oil leaks, and often-revved up cars put additional stress on spark plugs, so they suffer early wear-and-tear. That's all the more reason you need to replace them regularly to keep your engine--and vehicle--in good shape.