End result from forgetting to install this piece?

Can anyone tell me what the outcome of forgetting this part would be?

It sits on top of the manual shift lever on the valve body
(I think that's what it's called)
Its the arm basically near the solenoids
(A750E)

Of course I'm gonna drop the pan to install it but I'm just wondering if this could be the reason car is still not moving.

It shifts through the gears fine though, it just wont actually move

 

Not sure of the outcome, the piece has something to do with 'detent', it may be used to hold a valve in position. If you look on youtube.. A750E trans rebuild, vid shows a guy installing it before the filter. I'm not real good with computers, so I don't know how to upload the vid. Maybe you have already seen it, sorry I couldn't be of more help. If you take the pan off and reinstall, like you said.. 50/50, hope you get it going.

 

Did you get your trans. working? Just wondered if this detent was the culprit.

 

No.
The initial problem was that it would go into reverse, and reverse decently fine, but when put in drive, it would just rev really high and hardly even budge.

If u give quick taps o. The throttle, it'd work the best but still barely even go forward at all.

So I removed the valve body, and it was in poor shape, nearly even single valve was sticking etc.

So I removed them all and cleaned them really good and put it back together, but still had the same result.

Only now for whatever reason I'm getting noises from what sounds like the transmission or torque converter that sounds like high pitched "belt tearing" and whirring noises.

Both in park and in gear.

Haven't tried to see if the driveability increased cause I shut the car off pretty quick after hearing all that.

My untrained unskilled understanding is that it's a bad torque converter.

My assumption is that by cleaning the valves, it allowed more pressure to be built up within the transmission, which was the cause for these new noises.

I feel like originally due to the bad syate of the valves in the valve body, hardly any pressure if any at all was able to be made, but now after cleaning the valves, it's at least created some amount of pressure, but not enough to fully engage the gears. That's just my assumption

I got only 2 codes, which are solenoid d stuck off, and transmission slipping.

P2714 and p0894
If I'm remembering correctly.

Since I discovered I had forgotten this piece, I was just curious how important it was but if it is in fact the torque converter, I think my best bet would be to replace the entire transmission including valve body and torque converter