What are the reasons for the idle vibration of the Refine M3 engine?

[OCaroline]

The reasons for the idle vibration of the Refine M3 engine are: 1. Dirty throttle body; 2. Faulty spark plugs; 3. One cylinder of the engine not working; 4. Aging rubber components inside the engine mount and transmission mount; 5. Loose clamp or cracked hose on the intake manifold; 6. Leaking intake manifold gasket; 7. Damaged intake manifold or other components causing holes in the intake manifold. Extended content: Unwanted air, gasoline vapor, or exhaust gases entering the intake manifold can cause the air-fuel mixture to become too rich or too lean, leading to abnormal engine combustion. When the leak affects only certain cylinders, the engine may experience more severe vibration, especially during cold idle conditions.