Skip the auto shop - Our mechanics make house calls

How Can Problems with the Ignition System Cause Misfiring?

Dirty Spark Plug

Misfires are never good, and they're always a sign that there’s a problem with the engine that needs to be repaired. The problem won’t “go away on its own” and waiting too long can cause the situation to grow increasingly worse. Problems with the ignition system can definitely cause misfiring, and they can do so in a number of ways.

Possible causes of ignition-related misfires

The ignition system is responsible for igniting fuel in the engine's combustion chamber. If the system isn’t working correctly, the engine will misfire on one or more cylinders. Generally, only one cylinder is affected, but this isn’t necessarily always the case. What’s more, you may have misfires and not even know it, as wear on the ignition system components is gradual and mild misfires can be undetectable (although your Check Engine Light may come on, seemingly for no reason).

There are several potential ways that your ignition system problems could translate to a misfire:

  • Worn Out Spark Plugs: If your plugs are worn out, then the electrodes have gotten too short to provide the right amount of spark. This is a gradual process, and is the reason that you need to replace the plugs on a regular basis. If the wear becomes extreme, it’s possible that one or more plugs won’t fire at all, causing a misfire in the engine.

  • Damaged Spark Plug: Spark plugs are exposed to high heat and electricity, as well as vibrations. This can cause damage. If the ceramic insulator around the base of the plug is cracked or broken, it can cause a misfire.

  • Damaged or Failing Spark Plug Wires: If your car has spark plug wires (not coil packs), then the wires may be the source of a misfire. If the insulating coating on the wire has been compromised, it’s possible that the bare wire is touching a metal component in the engine and shorting out. This will cause a misfire. Another potential problem is an internal break in the wire – the charge won’t reach the spark plug and a misfire will result.

  • Dirty Spark Plugs: If a spark plug is fouled with carbon or oil, it may not spark properly, causing a misfire. This isn’t really an ignition problem, though. You’ll need to determine the cause of the carbon or oil buildup and repair it.

Problems with your ignition system can easily cause misfiring, but there are many potential causes. If your engine is misfiring, it’s vital to have the problem diagnosed and repaired by an experienced mechanic.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

Post a question and get free advice from our certified mechanics.

ASK A QUESTION

More related articles

How to Find the Keyless Code on a Ford Explorer or Mercury Mountaineer
Many Ford Explorers and Mercury Mountaineers were manufactured with an option known as the Ford keyless entry keypad. Some models refer to it as SecuriCode as well. It...
Insurance Requirements for Car Registration in Kentucky
The Kentucky Transportation Cabinet requires that all drivers in Kentucky carry liability automotive insurance, or “financial responsibility” in order to operate a vehicle legally and maintain vehicle...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...


Related questions

Q: Take key out car jeeps running sometimes. Then as oil and battery light want go off unless u take it slowly out

It seems as if your ignition switch is malfunctioning. Your ignition switch is the part that you stick your key into. This part is responsible for controlling different circuits based on the position of the key. It seems like the...

Q: Car in storage approx. 6 years. All checked over and ready for road; except engine misses

The Check Engine Light is the first thing to check. If you are getting a misfire code then inspect this cylinder and check the coil and spark to the cylinder. Once this is verified, make sure that the fuel injector...

Q: Car not starting when key turned

A battery starting charging system test should be performed by a qualified technician like the ones here at YourMechanic in order to see whether your battery has failed or if the problem is with a different system. Other issues such...