I believe it means that the pcm has corrected the idle downward as far as it can with the IAC and that there is no more room for adjustment. IIRC, the the IAC plunger is seated all the way closed and there is still more than enough air getting into the engine. Check for vacuum leaks around the intake and TB, PCV, and IAC. Is your TB stock or aftermarket. If aftermarket the hole in the blade may be too large. I filled mine and re-drilled a hole the same size as the SVT TB.
I think that is the same code I got when I first got my MAC 70mm TB before I fixed it up. I had to insert o-rings and grease at each side of the axial shaft that the throttle blade is on, right where they come through the housing because air was leaking in past the bearings. It fixed it nicely. Its nice that they use roller bearings because they wont wear out, but they are not sealed completely and the little bit of air leaking through them is significant on a duratech where it would not be significant on a big V8 which my TB was originally designed for.

warmonger


Former owner of '99 CSVT - Silver #222/2760 356/334 wHP/TQ at 10psi on pump gas! See My Mods '05 Volvo S40 Turbo 5 AWD with 6spd, Passion Red '06 Mazda5 Touring, 5spd,MTX, Black