Symptoms of bad spark plug could be embarrassing and as such should be given attention. So many car owners do not know what spark plug is all about. We will like to shed some light to what spark plug is, in order to appreciate this article to a maximum level. The spark plug is the component of your engine that is igniting the cylinder fuel/air mixture. The fuel injectors are injecting fuel into the combustion chamber and then the piston is compressing the air-fuel mixture. At this event, it’s time for the spark plug to ignite the fuel mixture to push the pistons down. If there is a problem with the spark, the air-fuel mixture won’t get ignited and it will blow out unburned through your exhaust pipe. That event is called a misfire.
Because of the importance of the spark plugs in the engine, there could be a lot of different symptoms on a car engine when you have bad spark plugs.
1. Engine Misfires
The most common symptom of bad spark plugs is that you will feel misfire from your engine. Misfires can cause the engine to run rough at idle, rough at acceleration and fuel economy changes. You check engine light will probably also show up after a while. You can feel the misfires as the engine will probably running rough and the engine sound may not be as it used to be.
2. Check Engine Light
When the engine is misfiring, the engine unit will often recognize the misfire and find out which the misfire occurs on and store it as a trouble code and lighten up the check engine light. Worn spark plugs or spark plug wires can trigger your check engine light. If a plug starts to fail then, the most obvious event should be the check engine light coming on or even flashing.
This can cause your engine to misfire and your check engine light to pop on. A flashing engine light could mean that potentially catastrophic misfires are taking place. In general, it’s best to replace spark plugs as part of preventative maintenance based on manufacturer’s specifications. This can help save you from costly repairs, as you driving with misfiring spark plugs could put undue stress on your car’s catalytic converter (the engine’s exhaust cleaner).
Symptoms of misfiring spark plugs include rough idling, uneven power when accelerating, and an increase in exhaust emissions.
Note that a check engine light could be potentially caused by a number of things, not just a spark plug problem.
3. Rough Idle
When a misfire occurs due to bad spark plugs, the unburned fuel may trick the O2 sensors. Then it will then regulate the fuel mixture and you may get a lean mixture. This can cause rough idle and even more misfires on other cylinders.
Due to the 02 sensor mentioned you can also get a slow and rough acceleration from misfires and lean mixture. You will often feel this at hard accelerations
4. Hard Starting Condition
Because of the importance of a good spark in the starting moment of an engine, bad spark plugs may cause the engine not to start at all or give you a very long cranking time before it will start. Your spark plugs have one of the most important jobs in your vehicle, which is to provide the spark that powers the engine! Old, worn out spark plugs have a harder time creating the spark that actually powers your engine. If your car stalls when you are trying to turn it on, there could be a problem with spark plugs or damaged spark plug wires. The battery is most likely the culprit if you’re hard starting at all.
5. Poor Fuel Economy
Because of the misfires and the O2 sensor regulations, you can get a poor fuel economy from bad spark plugs. This will most likely not be a dramatic difference, but it can be because a misfire can cause a lot of problems for the fuel mixture. When a spark plug works correctly, it helps burn fuel efficiently in the combustion cycle. When this occurs, your car can achieve better than average fuel economy. When the plug is not functioning optimally, it is frequently due to the fact that the gap between the spark plug electrodes is either too close or too far apart.
6. Slow Acceleration
The most common cause of poor acceleration on most vehicles is a problem in the ignition system. Today’s modern engines have sensors that tell the onboard computer and ignition system when to send electric pulses to fire the spark plug, so the issue may be with a faulty sensor. However, sometimes the issue is just as simple as a worn out spark plug. A spark plug is composed of materials that work together in order to produce a spark hot enough to ignite the air-fuel mixture. When those materials wears out, the effectiveness of the spark plug is reduced, which can significantly reduce the acceleration of the vehicle.
You’re probably pretty familiar with how your vehicle handles and drives. If you notice that your car isn’t as responsive as normal, particularly when you’re trying to accelerate, this could be traced back to worn spark plugs. It might be time to have them replaced—no one likes driving a sluggish, fuel-guzzling car.