R

RANDOM ACCESS MEMORY (RAM) - Computer memory that is not part of the permanent memory of the computer.
RATIO METRIC - As used in EEC-A voltage divided by the reference voltage (VREF) multiplied by 10.


REED VALVE (Courier) - Check valve used on some engine applications. Prevents reverse flow of air from exhaust manifold to intake air cleaner.


REFERENCE VOLTAGE (VREF) - Power supplied by ECA to some sensors regulated at a specific voltage (8 to 10 volts EEC-1,2,3 and 4 to 6 volts EEC-IV).


RELIEF VALVE - A pressure limiting valve located in the exhaust chamber of the thermactor air pump. It functions to relieve part of the exhaust airflow if the pressure exceeds a calibrated value.