Customer complaint may include MIL/Check Engine lamp on. Upon further inspection, fault code P219A - Bank 1 Air-Fuel Ratio Imbalance may be found in the powertrain control module (PCM) as pending, active, or stored. Other fault codes P1066, P1068, P106A, or P106C (Solenoid Valve Switch Off Time Out of Range) may also be stored. Customer may also complain about loss of power or engine running rough while P219A is active.