A decoupler assembly for transferring rotary movement between an engine driven shaft and a serpentine belt. The decoupler includes a hub configured to be assembled to the shaft. The hub has a helical first slot formed therein. A pulley is rotatably coupled to the hub. A carrier is mounted on the hub and includes a helical second slot formed therein, as well as an anti-ramp up boss formed thereon. A thrust plate is fixed to the hub and has a slot formed therein. A torsion spring is compressed between a hub end retained in the helical first slot and a carrier end retained in the helical second slot for transferring torque between the hub and carrier. The anti-ramp up boss travels within the slot formed in the thrust plate for limiting rotation between the carrier and thrust plate and preventing rotation of the torsion spring relative to the hub and carrier.