Newly rebuilt transmission hesitates from stop

[Zkroland]

I just got my car back from a year long medium restoration! Very happy but trying to pay attention to any strange behaviors. The two problems I seem to have: when sitting at a stop light the idle speed will surge a bit at about every 5-10 seconds. Doesn't come close to stalling, just annoying.
Then, when light goes green, I accelerate, reves go up, I hardly move, then after less than a second, it gets first gear with a bump and goes fine. It's not a bang, just a hesitation (not in engine, that is smooth) then it catches.
Any ideas would be appreciated. Thanks

[55Greg&Amy]

Check the tranny fluid first. My beater truck will do that when it gets low and I refuse to put anymore money in the old thing by fixing the leak.

[sseebart]

If the fluid is good, then sounds a bit like a vacuum leak.

~Steve