What Causes Multiple Cylinder Misfires in Cars?
2 Answers
Reasons for multiple cylinder misfires in cars are as follows: 1. Electrical wiring issues. 1.1 Aging or leaking electrical wiring, causing intermittent ignition faults. 1.2 Faulty ignition coils or spark plugs, resulting in poor ignition or conduction. 1.3 Loose wiring, exposed wires grounding, etc. 2. Fuel system issues. 2.1 Insufficient fuel injection pressure due to faulty electronic fuel pump. 2.2 Blocked or contaminated fuel lines, leading to poor fuel supply. 2.3 Faulty or clogged fuel injectors. 3. Engine-related issues. 3.1 Wear and aging, delayed maintenance, or use of substandard or low-quality engine oil. 3.2 Excessive wear causing cylinder pressure to fall below normal values. 3.3 Aging belts or incorrect ignition timing.
I've been repairing cars for over a decade, and multi-cylinder misfires are quite common. Most of the time, the problem lies in the ignition system - spark plugs with excessive carbon buildup or electrode erosion, aging high-voltage wires with leakage, or faulty ignition coils are frequent culprits. Last time I encountered a car shaking like it was dancing, and replacing the spark plugs immediately quieted it down. The fuel injection system also needs checking - clogged injectors causing fuel starvation or weak fuel pump pressure can also be issues. If the crankshaft position sensor fails, the control unit gets confused signals which easily leads to multi-cylinder shutdowns. Severe carbon buildup causing piston ring seizure can also cause this, making regular decarbonization essential.
