transmission

After a cold start if I back out of the driveway and put the car in D,
there is nothing there (Just revs up)
If I shift over to 1st, it drops into gear.
Only happens when cold.

Any Ideas?

Maybe you need to change the fluid and filter?

Could be a lot of things- but it is undeniable that most auto trannys are 'under maintained', even when following the recommended maintenance. A small bit of debris can be lodged in the valve body preventing the shift.