Common Symptoms of Faulty Spark Plugs

Most drivers understand to some level the importance of spark plugs in their engine, as they’re responsible for producing the electrical spark that ignites the air-fuel mixture within the combustion chamber.

With the constant use that spark plugs see, firing once for every power stroke of the piston, it’s no surprise that these components will gradually wear down over time. A single faulty spark plug can cause a host of issues within your powertrain, and could lead to more expensive repairs down the line if left to linger.

In this article, we’ll go over what spark plugs are, the common symptoms of failing ones, and what effect it could have on your vehicle. 

What Are Spark Plugs?

Spark plugs are a component in each cylinder of your engine that creates an electrical arc at a precise time to ignite the air-fuel mixture in the engine. Spark plugs fire once for every “power stroke” of the engine, which is the specific engine stroke where combustion occurs.

Symptoms of Failed Spark Plugs

Misfire

When one or more plugs fail, it could prevent them from producing the necessary spark needed for combustion. A cylinder that is unable to properly combust is known as a misfire, and not only can it disrupt the operation of your engine, it may even lead to more expensive repairs if not addressed immediately.

Catalytic converters become vulnerable when misfires occur, as unburnt fuel will be pushed into the exhaust system and could melt the internal structure of the converter. If you notice a misfire or a flashing check-engine light on your dash, it’s vital to have your vehicle inspected by a trusted professional as soon as possible to prevent any further damage to exhaust or engine components. 

Reduced Performance & Efficiency

Failed spark plugs may prevent the engine from operating efficiently, leading to a significant drop in performance and fuel economy. Fuel in the affected cylinders will be unlikely to fully combust, wasting gasoline and preventing your motor from producing the amount of power it should.

Rough Idle

As the engine is unable to properly combust the air-fuel mixture, it’s common for failing spark plugs to cause a rough idle. If your engine feels like it’s struggling to keep itself running while your vehicle is at idle, it’s possible that this is due to faulty spark plugs. 

Check Engine Light

While check engine lights can appear for a variety of reasons, an active light may be a sign of faulty spark plugs. Engine codes such as P0300 and P030X (“X” being the number of the affected cylinder) may appear to warn you of a misfire, which is often accompanied by a flashing check engine light. Generally, a flashing light is a telltale sign of a misfire, which could be the result of spark plug issues.

Spark Plugs & Powertrain Services at Sun Automotive

If you believe your spark plugs are on the way out, or notice an engine warning light, don’t hesitate to schedule your appointment with the experienced technicians at Sun Automotive. We have four locations across Eugene, Junction City, and Springfield, all equipped with the equipment and training to properly inspect, diagnose, and repair your engine.

Don’t let spark plug problems linger, as it could result in pricey repairs down the line. Give us a call or schedule online today to secure your appointment with our friendly team!