Hello everyone i drive a 2006 g35 coupe and my sport manual mode works flawlessly sometimes and other times ill be in manual and itll just sat D. Other times the manual mode will be working but then it will downshift a gear while moving at a constant spped. example-i was going like 45-50 and it went from 4th to third with out me telling it to then went from 3rd to 2nd. please help.