GDI Pump Control parameter

[Scott33]

What exactly is the "GDI Pump Control" logged parameter mean?  I assume it is the PID correction applied to the GDI pump control model (after utilizing all the lookup tables), and not the actual duty cycle of the GDI pump itself.

I haven't seen it list any values below -10% but I don't know if that means values <-10% simply aren't logged or whether the PID is clamped to -10%.

[TechDave]

8 hours ago, Scott33 said:

What exactly is the "GDI Pump Control" logged parameter mean?  I assume it is the PID correction applied to the GDI pump control model (after utilizing all the lookup tables), and not the actual duty cycle of the GDI pump itself.

I haven't seen it list any values below -10% but I don't know if that means values <-10% simply aren't logged or whether the PID is clamped to -10%.

Correct, it is the amount of effort the control PID loop is doing to meet target.

-10% indicates that the control loop is forever trying to remove fuel from the high pressure rail.

This might be due to a setup issue with your Pump Cam Lobe centerline, your Pump Calibration Table, Spill Valve Deadtimes, or the GDI pump compensation table.

Ideally GDI Pump Control should be near zero, or at least a steady value.