Hi thank you for your question. My name is ***** ***** I am a fully qualified technician with 30 years experience and hopefully i can help you.
As you have the codes this does make it easier.
The code P0562 indicates a low voltage and the code U2118 indicates a communication error with the CANbus system.
Given these two codes are both connected to an electrical problem I would first check the battery connections to ensure that both terminals and the earth points are clean and making a good connection.
If you can you should check the charging system to ensure this is working correctly.
The misfire may be occurring due to the low voltage in the system which prevents the coil from operating correctly.
The other common causes of a misfire are poor coil pack or spark plug, or injector problem. The electrical plugs on the injectors should be checked for any corrosion.
I hope this helps and answers your question, but do please feel free to ask any further questions.
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