What Causes a 3-Cylinder Misfire in an Engine?

[DeLeo]

There are many reasons that can cause engine misfires, which can be mainly divided into the following two aspects. Below are the explanations of the causes: 1. Caused by the damage of external components, mainly including the components around the combustion chamber such as valves, valve seat rings, valve guides, spark plugs, etc. Typically, you should check the spark plugs, clean the carbon deposits on the intake and exhaust valves, and inspect whether the turbocharger has any issues, such as wear or ablation of the turbocharger impeller. 2. Misfires caused by the failure to ignite or delayed ignition of the air-fuel mixture in the cylinder. This is usually due to an abnormality in a certain component or part, causing the ECU to regulate the engine unstably, failing to meet the theoretical values calibrated by the ECU, resulting in misfires.

[SanNadia]

I've experienced this situation before. When driving my own car, the engine shook violently, and after checking, I found out it was a misfire in cylinder 3. Common causes include a bad spark plug—over time, electrode wear or excessive carbon buildup can prevent it from igniting; a faulty ignition coil, which is responsible for delivering electricity to the spark plug—if it fails, it affects a specific cylinder; a clogged fuel injector, where a dirty nozzle can't supply fuel properly; and insufficient cylinder compression, such as from a leaking valve or worn piston rings, which reduces cylinder pressure. Other issues like short circuits in wiring or faulty sensors, such as the crankshaft position sensor, can also cause this. My advice is not to delay—first, connect an OBD diagnostic tool to check the trouble codes, confirm the issue, and then promptly take it to a professional shop for repair. Otherwise, fuel consumption may skyrocket, and the engine could suffer damage.

[AlainaAnn]

As someone who frequently tinkers with cars, I think there are quite a few reasons for a 3-cylinder misfire. The ignition system is a common culprit—spark plugs with excessive gap or cracked ceramic can cause ignition failure; aging coils with unstable output; stuck or dirty fuel injectors affecting fuel supply. In terms of compression, poorly sealing valves or leaking cylinder head gaskets reduce efficiency. There's also the possibility of ECU control signal failure or incorrect readings from the airflow sensor disrupting the air-fuel mixture ratio. Any of these can cause that cylinder to misfire. Diagnosis isn't hard—just plug in a scanner to read the data stream and pinpoint the specific cause. Don't try to fix it blindly; you might make it worse. It's best to take it to a reliable repair shop.

[Prim]

When the 3-cylinder misfires, my car shakes badly. Possible causes include worn-out spark plugs needing replacement, burnt ignition coils, clogged fuel injectors due to impurities, or insufficient compression like worn piston rings. It could also be an electrical issue with loose wiring connections. Get it checked immediately to avoid excessive fuel consumption and engine damage. A technician can diagnose it with a tester.

[VonAnna]

Having driven for many years, I know that a 3-cylinder misfire can be quite harmful. Possible causes include faulty spark plugs or ignition coils; issues with the fuel injection system such as leaking injectors; or compression problems like improperly sealing valves. Additionally, sensors such as oxygen sensors giving false readings can lead to incorrect air-fuel mixtures. Symptoms include engine shaking and excessive emissions. If left unaddressed, it may cause damage to the catalytic converter. For safety, it's best to stop the car, check the malfunction indicator light, and then use simple tools to diagnose the issue.