Well what a story i have. all started with rough idle in the cold mornings. was actually misfire in cylinder 3. turned out to be oil control valve. ( which is built into the VVT actuator ).The other day my car goes into LIMP mode on the highway in SPORT mode. happens every time now. so the whole actuator gets replaced bc its causing the misfire, i actually started knocking at some point ( just a worsened symptom of the bad VVT actuator ). then the O2 was bad causing limp mode, that was changed. I had a catalytic converter code saying it was clogged ( which also causes limp mode ) that was changed. now I just changed the MAP sensor ( which can also cause limp mode ) and the car STILL GOES INTO LIMP MODE!!! ( " limp mode only happens on the highway at high speeds and only in SPORT mode". I have checked the throttle body it opens and closes %100. I am stumped. Im guessing it has to do with the TCM? do you think that needs replacing now? or maybe an update? any ideas? anybody been through this problem? thanks!