BMW X5: Transfer Case, General

 Engine Adaptation Values

Engine adaptation values can be broken down into two categories: Additive Mixture Adaptation - additive adaptation refers to "long term fuel trim". These adaptation are made by the ECM (DME) at idle during "closed loop" fuel control. These values are measured in milliseconds and are expresse

 Boost-Pressure Control

The boost pressure of the turbochargers is directly dependent on the flow of exhaust gas which reaches the turbocharger turbines. Both the velocity and the mass of the exhaust-gas flow are directly dependent on engine speed and engine load. The engine-management system uses wastegate valves to co