This might add some more context FSM EF EC 27: There is an EGR solenoid. IIRC this is connected to a vacuum source (ie pre-compressor wheel in turbos) and operates in the aforementioned conditions. The ECCS (ECU) controls the EGR solenoid, which then actuates the EGR. It does not work on engine vacuum / boost alone. I'll let everyone get back to the physics of spring pressure and dick measurements.
