Closed Loop Mode

Open & Closed Modes Of Operation:

The engine will be in this mode when all the input data meets the programmed variables for Closed Loop Mode of Operation, and the output from the oxygen sensor is used by the ECM. This will result in an air/fuel mixture that will be optimum for the engine operating condition and also will correct any preexisting too lean or too rich mixture conditions.

NOTE: A low oxygen content in the exhaust indicates a rich air/fuel mixture, and a high oxygen content indicates a lean air/fuel mixture. The optimum air/fuel mixture ratio for the most efficient conversion of HC, CO and NOx is 14.7:1.