What are the symptoms of a faulty fuel injector?

[McJoel]

The symptoms of a faulty fuel injector include: malfunctioning fuel injector operation leading to severe carbon buildup in the engine cylinders, accelerated wear of cylinder liners and piston rings, resulting in unstable idling, increased fuel consumption, lack of acceleration power, difficulty starting the engine, and excessive vehicle emissions. In severe cases, it may even cause engine damage. A fuel injector is essentially a simple solenoid valve. When the electromagnetic coil is energized, it generates a magnetic force that lifts the needle valve, opening the injection port. Fuel is then sprayed at high speed through the annular gap between the needle valve tip and the injection port, forming a fine mist for optimal combustion. The main types of automotive fuel injectors include: diesel injectors, gasoline injectors, and natural gas injectors.