So I have an '01 Eclipse w/ the 2.4L and Sport Shift tranny. The other day, while in sport shift mode and upshifting from 3rd to 4th, the tranny just went neutral. I've researched on the internet and have read it could be anything from TCU to wavespring, but no one with similar symptoms ever posted what the fix was. So far I've tried to pull the codes from the TCU, but it isn't reporting any. I've checked the pump by pulling the cooler lines and it appears to be pumping fine. I even ohm checked the shift solenoids and all 5 checked in at 1.5. So, can anyone out there tell me what the problem is, or at least something else to check, before I pull the tranny? Any help would be appreciated. AND I'll be sure to post what the problem eventually turns out to be.