Have you checked the oxygen sensor connections on each side? Also
http://gl1800riders.com/forums/showthread.php?133958-gl1800-F1-Codes
http://gl1800riders.com/forums/showthread.php?184035-HIGH-IDLE-1800-gold-wing
http://www.goldwingowners.com/forums/showthread.php?t=8530
But this sounds alot like your issue.
http://www.goldwingfacts.com/forums/2-goldwing-technical-forum/394288-gl1800-idle-speed-2.html
http://gl1800riders.com/forums/showthread.php?133958-gl1800-F1-Codes
http://gl1800riders.com/forums/showthread.php?184035-HIGH-IDLE-1800-gold-wing
http://www.goldwingowners.com/forums/showthread.php?t=8530
But this sounds alot like your issue.
http://www.goldwingfacts.com/forums/2-goldwing-technical-forum/394288-gl1800-idle-speed-2.html