What are the causes of misfire in the third cylinder of a car?
4 Answers
The causes of misfire in the third cylinder of a car are: 1. Damage to external components, mainly caused by parts around the combustion chamber such as valves, valve seats, valve guides, and spark plugs; 2. Misfire caused by the inability to ignite or delayed ignition of the air-fuel mixture in the cylinder, usually due to abnormalities in a certain component or part, resulting in unstable ECU regulation of the engine, failing to meet the theoretical values calibrated by the ECU. A cylinder is a pneumatic actuator in pneumatic transmission that converts the pressure energy of compressed gas into mechanical energy. There are two types: those that perform reciprocating linear motion and those that perform reciprocating swinging motion. Cylinders that perform reciprocating linear motion can be further divided into four types: single-acting, double-acting, diaphragm, and impact cylinders.
When I encountered a misfire in the third cylinder, I found that the most common issue was with the ignition system, especially aging spark plugs or severe carbon buildup. Those slender spark plugs are particularly prone to wear under high temperatures, and if the gap becomes too large, they won't ignite. If the ignition coil's insulation is damaged and leaks electricity, it can also cause that cylinder to stop working. Another common issue is clogged fuel injectors, especially if you frequently take short trips, as impurities in the gasoline can block the injector nozzles. Insufficient cylinder compression is also critical—for example, if the valves don't seal properly or the piston rings are worn, a compression test will reveal the problem. Wiring issues can't be ignored either; if the wires controlling ignition and fuel injection get frayed, the signals can fail. Last time I inspected a car, the misfire was caused by a wiring harness that had been chewed through by rodents.
A misfire in the third cylinder is primarily related to three key aspects. First, regarding ignition issues, the condition of the corresponding spark plug is crucial. If it has reached the end of its lifespan or has excessive carbon buildup, ignition will fail. Next, examine the fuel system—clogged fuel injectors or unstable fuel pump pressure can prevent fuel from being properly injected, leading to combustion failure. Mechanical faults are often overlooked, especially valve sealing. Even slight deformation of the valve stem can cause air leaks, and worn piston rings can result in insufficient cylinder pressure. For electronic control, check both the driving signal of the ignition coil and the control signal of the fuel injector, as incorrect commands from the ECU can also cause misfires. It's best to address this issue immediately, as prolonged misfires can damage the catalytic converter in the exhaust system, significantly increasing repair costs.
When the engine indicates a misfire in the third cylinder, I would first check the ignition coil and spark plug. Try swapping these two components with other cylinders. If the issue follows the transfer, it indicates they are the problem. Fuel injector issues are also common—listen for a regular ticking sound during operation and use a multimeter to check if the resistance is normal. For wiring inspection, focus on the signal wires; unplug the connector to check for corrosion or oxidation on the pins. If there's a cylinder compression issue, it usually comes with symptoms of burning oil, and the exhaust will appear bluish. For daily prevention, it's recommended to replace spark plugs every 20,000 kilometers, use gasoline from reputable stations, and avoid prolonged low-speed driving to prevent carbon buildup.
