What was found
CREW REPORTED AIRCRAFT YAWED HARD LEFT WHEN SETTING TAKEOFF POWER. IT WAS TAKING FULL RIGHT RUDDER AND NOT MAINTAINING CENTERLINE. REJECTED TAKEOFF AND USED TILLER TO STEER AIRCRAFT BACK TO CENTERLINE. CREW RETURNED TO GATE. MAINTENANCE TROUBLESHOT AND FOUND NOSEWHEEL STEERING NOT RETURNING FULLY TO CENTER WITH TILLER HANDWHEEL. MAINTENANCE REMOVED AND REPLACED NOSEWHEEL STEERING TILLER AND PERFORMED CHECKS USING AIRCRAFT MAINTENANCE MANUALS. AIRCRAFT RELEASED FOR SERVICE.