20 kpa at 3k revs is this driven or static ?

try driving it and graph the pressure sensor , floor it in 2nd or 3rd to the red line and see what you get. 20 kpa is close to 3 psi, i know that at 27 kpa at WOT it will throw a code so you may still be restricted.

also i like to test the pressure sensor with a mitivac and look at it on the scan tool as i minipulate the sensor with the tool to see if it reads correctly you can do one side with pressure and the other side with vacumme .

do it a few times to see if it sticks