122 Data Parameters Gas Engine Parameters LEARN VALUE Orange not available) Indicates the operation and Long-term correction of the fuel delivery. It shows whether the ECM is commanding a rich or lean mixture. The number theoretically can range from -100% to 100% with 0% as the midpoint. A number above 0% indicates that the ECM has commanded an overall rich mixture correction. A number below 0% indicates that the ECM has commanded an overall lean mixture correction. Fuel correction operates only in closed loop. In open loop, a fixed value displays.