Can a Spark Plug with a Cracked Ceramic Still Be Used?

[DeAlexis]

Spark plugs with cracked ceramics cannot be reused. Below is an introduction to spark plugs: 1. The function of a spark plug is to introduce the high voltage generated by the ignition coil into the engine cylinder, creating a spark at the electrode gap to ignite the air-fuel mixture. 2. Although small in size, the spark plug has a complex structure, consisting mainly of two parts: the insulator and the metal shell. The metal shell is threaded for screwing into the cylinder, and inside the shell is the insulator, through which a central electrode runs. The top of the central electrode has a terminal nut to connect to the high-voltage wire from the distributor. The lower end of the shell is welded with a ground electrode, and there is a gap of 0.6 to 1 millimeter between the central electrode and the ground electrode. When high voltage passes through this gap to ground, it generates a spark to ignite the air-fuel mixture.

[DelMiguel]

When the ceramic part of a spark plug is cracked, I would absolutely never use it again. The ceramic is the insulating component; once cracked, the electrical spark can easily stray, leading to unstable ignition, engine misfires, or even stalling—this is no small matter. I've seen too many cases while repairing cars: some people think they can still make do with it, only to end up burning out the ignition coil, costing thousands to fix. Even worse, if the spark leaks to other areas, it can cause a short circuit and damage more electronic components. For driving safety, replace it immediately if you find cracks—don't skimp on the small cost. Replacing spark plugs isn't expensive, and you can either do it yourself or visit a professional shop—it's very convenient. Regular inspections are a good habit; check them every few tens of thousands of kilometers to avoid bigger troubles.

[Elliot]

Don't use spark plugs with cracked ceramic. I think once it cracks, it loses its insulation function. The electrical spark will scatter, directly affecting ignition performance, making the car hard to start and idle roughly. I've driven for over a decade—once ignored a tiny ceramic crack, and fuel consumption skyrocketed, nearly causing a breakdown. After replacing the spark plug, all problems disappeared. Ceramic cracks are usually caused by high-temperature aging or improper installation—don't forget to check during maintenance. Continuing to use it is too risky; for example, it might damage the ignition module, and the repair cost would be much higher than buying a new spark plug. Remember, safety first—replace it immediately if you find cracks, simple and worry-free.

[Violet]

If the spark plug ceramic is broken, I would definitely replace it and stop using it. The ceramic is crucial for preventing electrical leakage from the spark. If it's broken, it can lead to inaccurate ignition, poor engine performance, and may cause shaking or power loss. In the long run, not only will fuel consumption increase, but it could also damage other components. It's best to replace the spark plug with a new one promptly to ensure the car runs smoothly.

[LillianLynn]

The spark plug ceramic is broken, and I recommend replacing it immediately and not using it anymore. Because the ceramic is used for insulation, once it's cracked, the electrical spark may leak, causing unstable ignition or a risk of short circuit. This not only affects the car's performance, making the engine run unevenly, but also increases potential repair costs—for example, if the ignition system is damaged, the repair could be quite expensive. From an economic perspective, a new spark plug only costs between a few dozen to a hundred dollars, making it a worthwhile investment. Ignoring this small issue could lead to greater losses.