Manual rotation of throttle spindle
If it is necessary to increase the engine speed from inside the engine bay and the throttle spindle is rotated by mistake instead of the throttle arm, fuel shut-off will take place and diagnostic trouble code P1263 will be generated. Throttle control will not go into limp-home mode and CHECK ENGINE will not go on.
However, if the throttle spindle is rotated manually while the starter motor is cranking (e.g. during a compression test) or during the first 5 seconds after start, diagnostic trouble code P1251 will be generated and the system will go into limp-home mode.