The P208d engine code seems a kind of powertrain problem and this problem can be solved easily. The catalytic converter has an oxygen sensor what is set front and behind of the catalytic converter. When the vehicle is hot and running it in closed loop mode, the upstream oxygen sensor waveform reading should fluctuate. Deactivation of cylinders is realized by releasing a synchronizer pin that generally interlocks the cam follower and rocker arms. The engine P208d code tenacities the synchronizer pin is released using hydraulic compression which is controlled by an enthusiastic solenoid. You should read the car engine manual for solving the car engine problem.