automatic tranny prob...help please
 

my car is a 95 altima automatic and when i first start the car the transmission wont engage in D(drive) u can accelarate it and it acts like if it was in neutral.i checked the fluid and is not that. but when i put it in D1 or D2 IT WILL ENGAGE FINE,also any other gear will engage,except D (drive).what can this be,any help would be fine....