Context : Galaxy evolution scenarios predict that the feedback of star formation and nuclear activity ( AGN ) can drive the transformation of gas-rich spiral mergers into ( ultra ) luminous infrared galaxies and , eventually , lead to the build-up of QSO/elliptical hosts . Aims : We study the role that star formation and AGN feedback have in launching and maintaining the molecular outflows in two starburst-dominated advanced mergers , NGC~1614 ( D _ { L } = 66 Mpc ) and IRAS~17208-0014 ( D _ { L } = 181 Mpc ) , by analyzing the distribution and kinematics of their molecular gas reservoirs . Both galaxies present evidence of outflows in other phases of their ISM . Methods : We used the Plateau de Bure interferometer ( PdBI ) to image the CO ( 1–0 ) and CO ( 2–1 ) line emissions in NGC~1614 and IRAS~17208-0014 , respectively , with high spatial resolution ( 0 \aas@@fstack { \prime \prime } 5–1 \aas@@fstack { \prime \prime } 2 ) . The velocity fields of the gas were analyzed and modeled to find the evidence of molecular outflows in these sources and characterize the mass , momentum , and energy of these components . Results : While most ( \geq 95 \% ) of the CO emission stems from spatially resolved ( \sim 2 - 3 kpc-diameter ) rotating disks , we also detect in both mergers the emission from high-velocity line wings that extend up to \pm 500–700 km s ^ { -1 } , well beyond the estimated virial range associated with rotation and turbulence . The kinematic major axis of the line-wing emission is tilted by \sim 90 ^ { \circ } in NGC~1614 and by \sim 180 ^ { \circ } in IRAS~17208-0014 relative to the major axes of their respective rotating disks . These results can be explained by the existence of non-coplanar molecular outflows in both systems : the outflow axis is nearly perpendicular to the rotating disk in NGC~1614 , but it is tilted relative to the angular momentum axis of the rotating disk in IRAS~17208-0014 . Conclusions : In stark contrast to NGC~1614 , where star formation alone can drive its molecular outflow , the mass , energy , and momentum budget requirements of the molecular outflow in IRAS~17208-0014 can be best accounted for by the existence of a so far undetected ( hidden ) AGN of L _ { AGN } \sim 7 \times 10 ^ { 11 } ~ { } L _ { \sun } . The geometry of the molecular outflow in IRAS~17208-0014 suggests that the outflow is launched by a non-coplanar disk that may be associated with a buried AGN in the western nucleus .