E270 Limp mode code P0660

[DIYMAN]

Hi, my car went into limp mode two weeks ago so I tried putting some expensive diesel in to clean the EGR valve, that seemed to work until this week but now in limp again with nothing showing up on the display read the fault code, P0660 I understand this is a very general code so I guess it will need to go on a Star machine.
I am just posting it here in the hope that a member may have some advise on what to check, before I have to pay for that special coffee at the MB dealer.

 

[onefortheroad]

P0660 Intake Manifold Tuning Valve Control Circuit/Open Bank 1

How to quickly diagnose, repair, and causes of a P0660 diagnostic code which indicates a detected general fault or open condition in the intake manifold tuning valve control circuit on bank 1.

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