Patent Document ID: 9650977
Application ID: 14746551
Patent Flag: 1

Claim One:
1. An engine system, comprising: an engine including a plurality of cylinders; an exhaust gas sensor for estimating an exhaust air-fuel ratio; a pressure sensor for estimating an exhaust manifold pressure; a crankshaft torque sensor coupled to a crankshaft for estimating individual cylinder torque; and a controller configured with computer readable instructions stored on non-transitory memory for: determine a first confidence factor of the estimated exhaust air-fuel based on fuel type; determine a second confidence factor of the estimated exhaust pressure based on valve timing; determine a third confidence factor of the estimated individual cylinder torque based on exhaust temperature; indicate cylinder-to-cylinder imbalance based on two or more of the estimated exhaust air-fuel ratio weighted by the first confidence factor, the estimated exhaust manifold pressure weighted by the second confidence factor, and the estimated individual cylinder torque weighted by the third confidence factor; and apply an air-fuel ratio correction to one or more cylinders based on the indication.