What are the reasons for the engine malfunction light coming on right after maintenance?

[LaOscar]

The reasons for the engine malfunction light coming on right after maintenance are: 1. Poor gasoline quality leading to incomplete combustion of the air-fuel mixture in the cylinders; 2. Carbon deposits in the intake tract or on the piston tops causing poor atomization; 3. Excessive engine mileage weakening spark plug performance; 4. Faulty ignition coils. The solutions for an illuminated engine malfunction light are: 1. Promptly inspect the engine condition; 2. Check the status of vehicle sensors, mass airflow sensors, and spark plug components; 3. Examine whether engine knocking occurs; 4. Inspect ignition coils for faults; 5. Clean engine carbon deposits.