2005 S60 2.5T: Check Engine P0101 and rough idle after around 6 miles and restarts

[CorgB]

Previous errors were Intake and Exhaust P0026 and 0027.First had Intake and Exhaust Solenoid replaced with cheap aftermarket parts (Ebay), then put back in the original, cleaned Intake and Exhaust VVT Solenoids. Also engine flush and new oil. The related error codes went away.
Then rough idle got worse and had - due to P0100 -- ECM-120C and 120D -- Air mass -- Signal errors - the Mass Air Flow Sensor and the Turbo Intake Sensor replaced with quality parts.
Now, after driving few miles, switching engine off and restarting, Check Engine comes up with Engine Service Required and error P0101. Engine runs rough in idle, even stalls, misfires. This ONLY happens at restart.
The funny thing: Once the CEL is reset, idle is much smoother, but still not optimal - till I drive another few miles and restart.
Repair shop suggests to replace Solenoids with original parts (already ordered).

Anybody has heard of this? Thanks!