Is it normal for the engine to shake after cleaning the fuel injectors?

[LaMargaret]

It is normal for the engine to shake after cleaning the fuel injectors. The vehicle's onboard computer has a self-learning function. Before cleaning, the fuel injection data is stored in the ECU. If the injector nozzles are clogged with carbon deposits, the throttle valve will automatically increase its opening to ensure sufficient air intake during idle. After cleaning the throttle valve, the system still uses the data from when it was clogged, which can cause unstable idle and severe shaking due to the higher throttle opening. Simply resetting the throttle valve opening to factory settings will resolve the issue. The fuel injector itself is a normally closed valve. When the electromagnetic coil is energized, it generates suction, lifting the needle valve to open the nozzle. Fuel is then sprayed at high speed through the annular gap between the needle valve tip and the nozzle, forming a fine mist for optimal combustion.