Although most car owners can recognize many common engine problems, one of the things that is often confusing is misfiring. Since a misfiring engine can cause you to fail emissions checks, cost you more in fuel consumption, and lead to lacking power, it's important that you can recognize the signs and troubleshoot it. Here's a look at what you should know.

What Are the Signs of an Engine Misfire?

Changes in Exhaust Odor—When your engine misfires, it's not burning the fuel properly in the combustion process. That leads to discharging unburned fuel in the exhaust system. This is marked by a distinct odor of fuel in the exhaust.

Power Fluctuations—When your engine misfires, you'll notice that the power production of your engine fluctuates. As it hits the dead or misfiring cylinder, it will lose power due to the poor combustion. As it moves to the next functional cylinder, you'll feel a surge of power as the engine returns to normal function. This leads to jerking, jumping, and shuddering as the engine runs.

Sound Differences—If you listen closely, you'll notice a difference in how the engine sounds when you have a misfiring cylinder. The exhaust decibel will drop slightly with the exhaust from the misfiring cylinder, then it will return to full volume with the next properly firing one.

How Do You Troubleshoot A Misfire?

There are many things that can cause your engine to misfire. Knowing what to look for is the first place to start.

Spark Plug Problems—Each time your spark plug fires, it's going to burn away a fraction of the metal molecules on the electrodes. This will gradually erode the plug, increasing the gap between the electrodes. As the gap increases, it also increases the amount of voltage required to get the spark. This will eventually lead to insufficient voltage, which causes the misfire.

Plug Wire Wear—Over time, the resistance in the spark plug wires will increase. This is a natural occurrence due to use, but it will weaken the spark. In addition, cracks, wear, and other damage can also interfere with the function of the wires. Test the resistance on your plug wires regularly, and if one is bad, replace them all.

Fuel Supply Issues—Whether your injectors are clogged, weak flowing, or leaking, you'll run the risk of misfiring within the cylinders. Without the proper fuel supply in the combustion chamber, you'll end up with misfiring due to either running too lean or too rich. You'll need to have a mechanic test the fuel injection system to spot problems like these.

To learn more about auto repairs, contact companies like Engel's Auto Service & Towing.

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