What Are the Symptoms of Bad Spark Plugs?

Every car owner wants their vehicle to perform at an optimal level and in order to achieve this goal, proper maintenance must be applied to every part of the car — even to the unassuming spark plugs. A spark plug may be small, but it is an incredibly important piece of equipment: Its job is to start the car. The spark plug does this by creating a spark which in turn ignites the air-fuel mixture in the combustion engine.

The spark plugs send the engine's pistons into action, and then they go on to provide the power necessary to keep the vehicle in motion as it makes its way down the road. Timely and appropriate car care not only improves a vehicle's life span, but also creates a much better driving experience overall. If a car owner forgets to take their car in for a regular tuneup, the vehicle may start to exhibit signs that it needs some attention. We at Tom Kadlec Kia hope these car care tips help car owners in the Rochester area learn when it's time to get their spark plugs replaced (or at least cleaned).

The Car Has Trouble Starting

Image via Flickr by Kevin Reese

When a car will not start, usually the battery is thought to be the aggravating cause behind this issue; however, the spark plugs should also be high on the suspect list. If spark plugs have become clogged or worn down, the car's engine has to work overtime in order to make up for the overworked plugs. Sometimes the car will not start at all because there is simply not enough spark created to turn the engine over. When the spark plugs are in this sad state, even harsh weather conditions can keep the engine from turning over.

The Engine Idles

An engine's failure to turn over is not the only sign that the spark plugs are in dire need of replacement. If a car owner hears that the engine is emitting annoying knocking and rattling sounds, they should not put off inspecting it. These sounds mean that the car's engine is roughly idling. When the car does this, it is a definite sign for the car owner that it is time to, at the very least, schedule an appointment to have the spark plugs checked out by a professional.

The Car Fights to Accelerate

Imagine that a car owner is traveling down the road and then tries to accelerate but the car won't respond. Not only does this create a very dangerous predicament, but it also should alert the owner that the car needs to be seen by a mechanic. The car's failure to accelerate is a very obvious sign that the spark plugs need to be replaced. Such scenarios can be avoided through scheduling regular car checkups.

The Engine is Very Loud

No matter if you drive a car with a four-, six-, or eight-cylinder engine, a really loud noise coming from the engine should let you know that at least one of the spark plugs is acting up. When the spark plugs malfunction, they reduce the effectiveness of the engine's cylinders, which then causes the cylinders to rattle. These unpleasant noises indicate that the cylinders are being overworked and will lead to further troubles down the line.

The Engine Misfires

Many things can cause an engine to misfire, like inferior quality fuel or leaky valves, but those offenders may not be the only causes behind this particular issue though. An engine misfire can often be the result of at least one timeworn spark plug. When this happens, a car owner will notice that the engine pace wavers but then catches back up. They may also hear a "pop" from the engine when it falters before recovering the proper timing. When a vehicle misfires, raw fuel is sent into the exhaust. Ultimately, this causes damage to the catalytic converter and can result in costly repairs.

The Vehicle gets Poor Fuel Economy

Replacing a catalytic converter isn't the only thing that can cost a car owner money due to poorly maintained spark plugs. When the plugs are in poor condition, they can't burn the fuel in the combustion chamber in a productive manner. When this occurs, the car needs even more fuel more often in order to perform properly, resulting in poor fuel economy. Because of this, a car owner will notice that the engine isn't the only thing that's put through extra work when the spark plugs are worn out. Those deteriorated plugs will cost a car owner plenty of money as they have to buy more and more fuel.

The "Check Engine" Light is On

The internal system of a car has tools in place to alert even the most forgetful car owner that a car maintenance appointment needs to be scheduled. When a spark plug has become slathered in oil and carbon or is even blistered from running too hot, it can cause a slew of problems for the engine. Paying attention to the check engine light can be incredibly helpful. This light serves as a warning and signals that it's time for a car owner to call a mechanic even if no odd noises are not yet coming for the engine.

The main point every owner of a car should take away from this article is to be aware of the car's preemptive warning signals. It is easy to pass over a routine maintenance appointment but when the vehicle sounds off its alerts, it is in a car owner's best interest to pay attention. The one thing a car owner can always bank on is this: failing to clean or replace overworked spark plugs can result in costly repairs that could have been avoided.