I have seen both code come up if there is air leak or some loose contact in my M111 (Assuming all sensors are fine.)

1) Re-check and clean AMS connector contact points.
2) Check if there is leak @ IAT plug.
3) If there is breather that goes into intake/crosspipe from cylinder head cover, check for crack.
4) Check vacuum lines.
5) Check brake booster vacuum line, it has one way valve which can leak (for testing just disconnect brake booster pipe, block it temporarily clear codes and check).
6) Check purge valve lines for leaks, check if purge valve itself is stuck open, you should not be able blow air through it when removed. Purge valve operates @ temp > 80, you can feel it ticking if you touch it.

I have seen only blocking purge valve line for testing will not work, since purge valve is electrically connected, ECU's fuel injection timing will be as if purge valve was working. Blocking purge and disconnecting it electrically should work, but ECU puts up error code for purge valve connection open.