-code 14, EACV

What do u know about code 14? i have it and i tried to rewire the IACV, replace it with one that was thoroughly cleaned (reusing o-ring gasket), two other ECUs and still nothing. any ideas? whenever i run it to 8000 rpms, it'll go into limp mode. but until then it seems to drive pretty good. at lower rpms/speeds, its a little tough to drive because theres no medium between 0-10% throttle so it bucks a little, but on the highway it drives great. any ideas?