Another often overlooked component that’s absolutely vital to your vehicle’s performance is spark plug wires. They carry the spark to the spark plugs, which starts the fuel air mixture of your vehicle’s engine.
When your spark plug wires wear out or start to deteriorate, you can literally run into all kinds of problems with the performance of your engine.
By learning to recognize the warning symptoms of bad spark plug wires (before it’s too late), you can avoid major repairs and keep your vehicle running smoothly and efficiently over the road.
This article will teach you the most common warning symptoms of bad spark plug wires.
Article Summary
Symptoms of Bad Spark Plug Wires
Although spark plug wires aren’t usually considered when it comes to your vehicle’s performance, they actually play a significant role.
They deliver electricity to your spark plugs from the ignition coil to ignite the fuel and air mixture in your engine.
When your wires go bad, you will start to experience a host of symptoms that will affect your vehicle’s performance and fuel mileage. Here, we’ll go over the signs of bad spark plug wires.
1. Engine Misfires
Among the most obvious symptoms of bad spark plug wires is misfiring. If your wires are bad, they won’t be able to send the spark that picks up the fuel air mixture in any one of your cylinders, so the combustion will be incomplete.
Thus, the engine will misfire, and you might feel a jerk or stumble while accelerating, and the check engine light flashes.
2. Rough Idling
If your car is idling rough, you might need to get a new set of spark plug wires because they could be shorting out, causing an uneven spark.
When your engine starts to idle roughly, you might feel excessive vibration or hear what feels like a rough, uneven sound.
3. Reduced Fuel Efficiency
The lack of right sparks from improperly plugged wires corrupts fuel economy. Again, when the fuel and air are not ignited, the fuel escapes without being burned, becoming waste.
As you top off more frequently, you begin to put more fuel in the tanks (gasoline) than you used to.
4. Difficulty Starting the Engine
Bad spark plug wires can make starting your car difficult. Spark plug wires connect the spark plugs in your engine to the rest of the power system.
If the wires are bad, they may not allow the spark plugs to fire when they should, making your vehicle difficult to start. You might notice that the engine will crank but not start or that it just takes longer than usual.
5. Poor Acceleration
Poor acceleration can be a sign of bad spark plug wires. If not enough spark is delivered, acceleration will suffer, and the engine will not work as well, leading to less overall power and a noticeable difference in performance.
6. Visible Damage to the Wires
Other times, bad spark plug wire symptoms are apparent. Check the wires for cracks, burns, corrosion, or other signs of excessive wear.
Damaged wires can’t transfer the electrical current cleanly, and you’ll end up suffering from the issues listed above.
7. Engine Surging
In addition, when the spark plug wires need replacing, it can be accompanied by a symptom known as engine surging. When an engine surges, it speeds up and slows down.
For example, when a troubleshooting app tested the spark plug wires on a 2009 GMC, they found that it produced high rpm surges, as well as power loss.
Since bad spark plug wires can lead to inconsistent firing of the cylinder, which leads to engine surging and power loss, these are indicators that there may be trouble with the spark plug wires.
How To Fix If You Suspect Bad Spark Plug Wires
If you have any of these problems, try to deal with them as soon as possible. To sum up, here are some things you can do:
Check the Wires: Look for rips and cuts. If you see them, it’s a good idea to replace the wires.
Check Fault Codes: If the check engine light is on that could be a sign that the trouble is in the ignition. Assess the warning lights to determine if the issue is with the ignition system.
Wires Can Be Replaced: If you find that the wire is the culprit, replace the wires with unitized replacement wires made for your vehicle.
If you have any doubts, see a professional. If you are unable to diagnose and treat the problem yourself,
How To Maintaining Spark Plug Wires
Regular Inspection: Perform regular visual inspections of your spark plug wires for cracks, burns, and corrosion. If the damage is severe, you could be dealing with a meltdown.
Routine Maintenance: Replace spark plug wires every 30,000 to 50,000 miles as recommended by your vehicle manufacturer. Regular maintenance of the ignition system is essential for good performance and long life.
Avoid Exposure to Fluids: Don’t put spark plug wires in direct contact with oil, coolant, or other engine fluids. These substances degrade wire insulation.
Proper Handling: When doing any mechanical work on your vehicle, handle your spark plug wires carefully. Do not pull on the wire itself when trying to unhook a wire. This damage can seriously shorten the life of your wires. Use just the boot and unhook.
FAQs on Symptoms of Bad Spark Plug Wires
How Often Should Spark Plug Wires Be Replaced?
Spark plug wires are generally recommended for replacement every 30,000 to 50,000 miles. Although this is dependent on your specific make and model, location, driving style, and conditions and quality of your wires. Consult your vehicle’s owner manual for specifics.
Can I Drive with Bad Spark Plug Wires?
It can be driven with a poor spark plug wire, but that’s not a good idea. Problems include engine misfires, decreased fuel economy, and damage to related engine components, and the vehicle will never achieve its Manufacturer’s performance benchmarks. The wisest course is to perform a replacement when any symptoms appear to eliminate any further issues.
What Causes Spark Plug Wires To Go Bad?
Spark plug wires can fail from heat, age, or damage from oil or other engine fluids. The insulation can crack, burn, or corrode, causing them to stop working.
How Can I Test Spark Plug Wires If They Are Bad?
You can also check spark plug wires with a multimeter. A spark plug wire is a lead that brings electricity from your ignition coil to your cylinders. You can test spark plug wires to see if they have the correct resistance. Shut off the engine, disconnect the wire, and set your multimeter to the appropriate range (often in ohms). Put both probes on the wire to be tested one on either end and then read out the resistance against the manufacturer spec for your particular vehicle in your vehicle’s service manual. A resistance much lower or higher is a defect.
Can Bad Spark Plug Wires Affect Car’s Fuel Efficiency?
Spark plug wires can affect fuel efficiency in your car. When you have bad spark plug wires, combustion can be incomplete, hence wasted fuel, which in turn translates into fewer miles per gallon. Replacing those bad spark plug wires can help you gain your fuel mpg back.
Conclusion
A bad spark plug wire can cause many engine performance issues that will alert you to the problem through symptoms such as misfiring, running rough, poor fuel economy, or even difficulty starting. Often, a failure can be missed.
Considering this, it is important to be aware of the symptoms of a failing spark plug wire so that when they do occur, they can be acted upon before the system fails.
It is important to perform regular checks of the spark plug wires to ensure proper operation and replace them as per the Manufacturer’s recommendations.
