Abstract: Methods and systems are provided for an EGR system. In one example, a system comprises a first turbocharger configured to increase an intake gas pressure and a second turbocharger configured to increase an exhaust gas pressure. The second turbocharger is dedicated to only compressing exhaust gases flowing to an intake passage.

Abstract: Methods and systems are provided for an EGR system. In one example, a system comprises a first turbocharger configured to increase an intake gas pressure and a second turbocharger configured to increase an exhaust gas pressure. The second turbocharger is dedicated to only compressing exhaust gases flowing to an intake passage.

Abstract: Methods and systems are provided for controlling a wastegate coupled to a turbine. In one example, a method may include during steady engine operation, actuating a wastegate to introduce an oscillation in boost pressure, and updating gain of a wastegate feedback controller responsive to the oscillation in boost pressure.

Abstract: Methods and systems are provided for adjusting an exhaust gas recirculation (EGR) valve based on a final EGR estimate. In one example, a method may include adjusting the EGR valve based on a final EGR flow estimate, the final EGR flow estimate based on a first EGR flow estimated with a differential pressure sensor across the EGR valve, a second EGR flow estimated with an intake oxygen sensor, and accuracy values of each of the first and second EGR flows. The accuracy value may be based on engine operating conditions during estimation of the first and second EGR flows.

Abstract: Methods and systems are provided for controlling a wastegate coupled to a turbine. In one example, a method may include during steady engine operation, actuating a wastegate to introduce an oscillation in boost pressure, and updating gain of a wastegate feedback controller responsive to the oscillation in boost pressure.

Abstract: Methods and systems for correcting cam angle measurements for engine-to-engine build variation are disclosed. In one example, a method comprises learning cam angle corrections to update a measured cam angle responsive to air-fuel ratio errors during selected conditions, and learning air and fueling errors responsive to the air-fuel ratio error otherwise. In this way, cam angle errors due to engine build variation may be corrected, thereby improving other air and fuel adaptation methods and improving engine emissions.

Abstract: A vehicle includes a transmission and a controller. The controller is configured to receive a torque request, calculate a Specific Fuel Consumption (SFC) for satisfying the torque request in an initial gear and in an alternate gear, and command the transmission to shift from the initial gear into the alternate gear in response to the calculated SFC for satisfying the torque request in the alternate gear being less than the calculated SFC for satisfying the torque request in the initial gear.

Abstract: A vehicle includes a transmission and a controller. The controller is configured to receive a torque request, calculate an SFC for satisfying the torque request in an initial gear and in an alternate gear, and command the transmission to shift from the initial gear into the alternate gear in response to the calculated SFC for satisfying the torque request in the alternate gear being less than the calculated SFC for satisfying the torque request in the initial gear.

Abstract: Methods and systems are provided for adjusting an exhaust gas recirculation (EGR) valve based on a final EGR estimate. In one example, a method may include adjusting the EGR valve based on a final EGR flow estimate, the final EGR flow estimate based on a first EGR flow estimated with a differential pressure sensor across the EGR valve, a second EGR flow estimated with an intake oxygen sensor, and accuracy values of each of the first and second EGR flows. The accuracy value may be based on engine operating conditions during estimation of the first and second EGR flows.

Abstract: Methods and systems for correcting cam angle measurements for engine-to-engine build variation are disclosed. In one example, a method comprises learning cam angle corrections to update a measured cam angle responsive to air-fuel ratio errors during selected conditions, and learning air and fueling errors responsive to the air-fuel ratio error otherwise. In this way, cam angle errors due to engine build variation may be corrected, thereby improving other air and fuel adaptation methods and improving engine emissions.

Abstract: A method for compensating for thermal transient conditions of an engine that can cause valve growth or contraction is disclosed. In one example, the method provides cylinder air amount compensation during non-blow-through and blow-through conditions. The approach may improve cylinder air amount estimates, thereby improving engine emissions.

Abstract: A system and method for controlling first and second phase shiftable camshafts in a variable cam timing engine is provided. The method includes determining when the first camshaft is moving toward a first scheduled phase angle with respect to the crankshaft with a larger camshaft angular positioning error than the second camshaft. Finally, the method includes slowing down the first camshaft so that synchronized camshaft positioning can be better achieved.

Abstract: A system and method for controlling first and second phase shiftable camshafts in a variable cam timing engine is provided. The method includes determining when the first camshaft is moving toward a first scheduled phase angle with respect to the crankshaft with a larger camshaft angular positioning error than the second camshaft. Finally, the method includes slowing down the first camshaft so that synchronized camshaft positioning can be better achieved.