Hi everybody,

I am looking for explanations on how to read an EGR map :
the X and Y axes correspond to engine speed (RPM) and IQ (mg/stroke), but what do the values ​​on the Z-axis represent?
They aren't percentages.
VAG EDCSuite says it is the MAF, but I don't understand why.

Depend on ecu. Usually axes are rpm and IQ and data desired mg/i.

But this EGR map is used to provide the signal to open or close the exhaust gas recirculation valve—is that right?
So why would the Z-axis be in mg?

Logically, we should be seeing a valve opening percentage, or something like that.

EGR has % map too and PID to control flow.

What is it "PID" ?

Control routine to match desired value and error if not.