DV check on the Ed is relatively simple as it's right at the front of the engine.
Still don't understand why you are getting the System too Rich code.
17705/P1297/004759 - Pressure Drop between Turbo and Throttle Valve (check D.V.!)
Possible Symptoms
Malfunction Indicator Light (MIL) ON
Power Loss
Possible Causes
Leaking Hoses and/or Pipes between Components
Boost Pressure Control Valve (N249) faulty
Diverter Valve faulty
Throttle Body dirty
Possible Solutions
Check Hoses and Pipes between Components
Check / Replace Boost Pressure Control Valve (N249)
Check / Replace Diverter Valve
Check / Clean Throttle Body
Perform Throttle Body Alignment
Special Notes
Did anyone install an extra (wrong) dump valve?
When found in the NAR 2.0T (BPY) check RVUTB: 01-09-03 or 2018919 for updated Crankcase Breather Valve
If the breather valve is faulty, full engine vacuum is typically found when removing the oil cap at idle.