For quite a long time my Stang has had an issue with stalling out when pushing the clutch in when stopping or just getting ready to downshift. The problem didn't happen all the time, but happened enough to tick me off. I originally had an automatic and swapped in the T5. When I started asking about the stalling issue a majority of people told me it was because of the auto EEC and I needed one for the manual. Ford Racing advised me to keep the A9P EEC in it, and sent me instructions to set the idle, still the problem was there. I was told it could be the IAC, replaced it twice, along with the TPS. It still would stall. One day Nicole sent me a link to a thread about surging idle ( http://forums.stangnet.com/showthread.php?t=534062 ) and said that it might be the Varible Speed Sensor causing the problem. I crawled under the car and saw I had nothing hooked up to the VSS on the tranny and nothing to connect to it. Come to find out, the wiring harness that was hooked up to the tranny was for a 5 spd w/out cruise control, so no VSS wires. I was able to order the right harness and installed it. I took it for a test drive and finally there is no stalling and it even idles better. Thanks for pointing me in the right direction Nicole.