EJ6 automatic transmission issues.
 

Hey everyone, I'm back once again with some troubleshooting for my car. I've been having this issue for a while now, and I'm at my wits end trying to figure out what the solution to the problem is.

Basically, when my car is warmed up and I'm in D3 at a full stop and try to take off again, the car will move (slightly) but the RPM's sky rocket (from what I can hear, no tach) until my car goes fast enough to upshift into second gear. However if I manually shift the car into 2, it takes off just fine.

Now, the way I would describe it is almost like a slip, but not entirely. I noticed when I am coming of the freeway and shift from D4 into D3, I feel the car downshift to 3rd gear, but then I don't feel it drop into second OR first, which is why I feel that my car does not shift properly from 3rd to any lower gear. Again, this is only at operating temperature, not while cold. When it's cold, it takes off just fine in D3. While we're on the topic of freeway driving, my car often will stay in 3rd gear when it should be in 4th or Overdrive.

I've replaced a solenoid on the side of the transmission housing, I've replaced what I think is the input speed sensor (however I got the WRONG part, it looks right but won't properly clip in), and I've also done a transmission flush and fill. None of these improved the performance of my transmission. As you can probably tell, I've done everything I can do at this point, aside from spending ANOTHER $130+ for another solenoid/sensor. IF it's not an internal transmission problem, all I can think of replacing would be the ACTUAL input speed sensor or the shift lock solenoid.

So, what do you guys think? Is my transmission shot or can it be salvaged?

Edit; For the record, it's a 1997 DX.