What was found
WHILE AIRCRAFT WAS IN HEAVY CHECK MAINTENANCE FOUND THE EMERGENCY ABSORPTION SYSTEM QUADRANT PLUGS INSTALLED INCORRECTLY, AND DAMAGED ON SEATS 8D, 10CD, 13D, 14D, 15D, AND 17D. MAINTENANCE REMOVED AND INSTALLED THE QUADRANT PLUGS IAW EMB 170 CMM 25-22-50. THE AIRCRAFT IS OUT OF SERVICE IN HEAVY CHECK.