I have a 1998 Accord, v6 with auto trans. Have had it since late spring, runs great trans shifted great. Now that it is colder, 50 or less the trans shifts kinda hard coming out of the first few gears, maybe hangs a little in a gear also before shifting, clears up after about a few miles and does not come back till it sits all night in the colder weather.
Trans was rebuilt back in 2013 or so the PO (only owner) says. Based on miles of car and how many he put on it a year that rebuild has about 20-30k on it. The fluid it nice and red and showing on dipstick correctly.
I am getting the flashing green light around D4 I think it is. I assume that is thrown codes from Trans, indicator? What could it be since this thing was just rebuilt so few miles ago?

 

Based on the miles of the car and the PO having owned it all it's life till this past spring he put only about 6600 miles a year on it.

 

I had a shop look at it. No codes stored. Says the Trans is in fine shape. I am told the trans has to set off the problem 3 times in a row. Is that in the same drive? Or over a certain period of time or what?
The car did not act up for them while they had it this morning in 50 degree weather which I figured it would not.
When it gets down below 45'ish it will shift through the first few gears funky then. Go a mile or two then it clears up.

 

Now that it is MUCH colder, it is very quirky in shifting, speacially out of the first few gears, it seems to hold a gear too long making it rev up then a FIRM shift into the next gear. When it down shifts it has the firm shifts there also where as when the car is warm to running temps it shifts more like I would expect. Is this car just not liking the cold weather? When I had the timing belt down they said the fluid was nice and pink/red and was not low.
I am not seeing any warning lights or anything. About the only way around this trying to keep the small rev/firm shift is to drive the car normal/a little slower until the car is warmed.