qualifier: i have no experience or knowledge with "custom tunes"....ecm jibberish....or hot-rodding an XB motor. having said that a typical XB "hanging idle" issue....assuming the cables are lubed and adjusted properly and sufficient slack is dialed into the puller cable is the result of 1 or more of the following:
1-tps in need of reset along with curb idle adjustment to 1000 rpm on pre 2008 models
2-warm motor curb idle speed set too high
3-faulty neutral sensor safety switch.
