When asking for technical help at the very least let us know the version of firmware you are running.Cliff's Calibration (Mapping) Guide is a MUST READ: http://www.vemssupport.com/forum/index.php/topic,97.0.html
I've found that the IACV clatters on a few of the installs that I've done, its one of those 'features' that goes away if you turn the ignition off. One of the spare 1N4004 diodes would be worth trying.