Virgo and Checkboard have got it right, as applied to a supercharged (not turbocharged) engine, and provided the fine pitch limit is not reached. Virgo's reference to submarines suggests that he is an ex Shackleton man, as I am.
If the fuel supply to an engine was cut, there would be a momentary dip in the RPM as the CSU compensated for the power loss, but it would return to its original RPM. The MAP would also dip and return, since the supercharger speed was related to engine RPM. The oil pump being engine driven, the oil pressure would be maintained.
If you missed seeing this brief dip, you were then faced with yaw and reducing airspeed. It would be some time before coolant temperature would show, as the radiator flaps would normally be in auto, and would close to maintain the temperature.
Having decided which side the failed engine was (i.e. dead leg), and after increasing power all round, the procedure was to close the throttle of the
inboard engine on that side, while watching the RPM gauge.
If the RPM dipped, that was the good engine, going from thrusting to windmilling. Restore the power on it promptly, as you are now double assymetric.
If the RPM did not dip, it was because that engine was already windmilling, i.e. it was the failed engine, so go ahead and feather it.