What are the causes of engine cylinder misfire?
3 Answers
Engine cylinder misfire can be caused by: 1. Spark plug clogging or damage; 2. Issues with cylinder wires; 3. Problems with the ignition coil; 4. Fuel injector clogging or low voltage, leading to loss of fuel injector data within the DME; 5. Issues with the air-fuel mixture; 5. Problems with cylinder pressure. Engine cylinder misfire can have severe consequences for the engine. After misfire, high concentrations of hydrocarbons enter the exhaust system, causing excessive tailpipe emissions. High hydrocarbon concentrations can also increase the temperature of the catalytic converter, potentially damaging it in severe cases.
As a seasoned driver with over 30 years of experience, I've encountered numerous engine cylinder misfire issues. The main culprits are ignition system failures—spark plugs fouled with excessive carbon buildup or overly wide gaps that prevent proper ignition, or aging ignition coils unable to deliver sufficient energy. The fuel system is equally critical; clogged or leaking fuel injectors can starve the cylinder of gasoline. Compression problems like poor valve sealing or worn piston rings result in insufficient pressure for combustion. Faulty sensors such as the crankshaft position sensor can throw the ECU's control into disarray. Even minor ECU software glitches may cause misleading ignition timing. When misfires occur, I notice the engine shaking violently like a sieve, with black smoke from the exhaust and skyrocketing fuel consumption. Left untreated, the catalytic converter will inevitably fail. I always recommend regular spark plug replacements and using a compression gauge to check pressure differentials. Addressing issues early saves big money—don't wait until the vehicle breaks down to regret inaction.
I enjoy tinkering with cars and often deal with cylinder misfires. Dirty or burnt spark plugs are the most common causes, and replacing them usually solves the problem. A faulty ignition coil that doesn't transmit electricity or damaged high-voltage wires can also be culprits. On the fuel side, injectors clogged with carbon deposits or insufficient fuel pressure can prevent ignition in the cylinder. Low compression, possibly due to deformed valves or cylinder wear causing leaks, is another issue. Sensor failures, like an oxygen sensor sending incorrect signals, can make the ECU adjust the air-fuel ratio improperly. Misfires are harmful—the car jerks during acceleration, making it dangerous and prone to accidents. I usually use a Bluetooth OBD scanner plugged into the car to read fault codes, identifying the misfiring cylinder in a minute. Replacing spark plugs myself is cost-effective, and professional tools aren't expensive—DIY is fun. It also saves fuel and protects the environment; don't underestimate emission issues.
