What are the reasons for persistent multi-cylinder misfires?
2 Answers
Persistent multi-cylinder misfires can be caused by the following reasons: Ignition failure: It is necessary to check the ignition coils and high-voltage wires. Ignition coils cannot be repaired; they must be replaced if damaged. Fuel injection failure: This may be caused by wiring issues or poor fuel injection pressure. Check cylinder pressure and the timing system. Inspect the crankshaft position sensor, which is often overlooked. Human error: Such as carelessness or mistakes during repairs, loose connections, or disturbed components leading to malfunctions. Wear and aging: Lack of timely maintenance or the use of substandard, unqualified, or non-compliant engine oil. If the engine malfunctions, replace it promptly.
Oh, I've encountered this issue before, and it's indeed tricky to fix. There are numerous reasons for persistent multi-cylinder misfires. Weak sparks caused by aging ignition coils or incorrect spark plug gaps can prevent multiple cylinders from firing properly. Sometimes it's the fuel system causing trouble—clogged fuel injectors or insufficient pressure may prevent fuel from entering the cylinders. Faulty sensors, like a damaged mass airflow sensor or oxygen sensor, can also mislead the ECU into sending incorrect commands. Don’t overlook loose or corroded wiring connections, which can cause unstable current flow and make the problem even more frustrating. Worse yet, system integration failures, such as module programming errors or compatibility issues, are often hard to detect with standard diagnostic tools. Every time I tackle this, I start by checking the basics, but hidden defects can be time-consuming and labor-intensive. I recommend seeking professional scanning diagnostics early on—delaying repairs could affect engine lifespan and fuel efficiency.
