I checked the MAF sensor and it get 12V but the input wire stuck on 2.3V , and it not move , even i open the throttle body.

Are you talking about the MAP sensor?

The MAF cannot be measured in volts, you have to have a multimeter capable of reading hertz.
Or one like an Actron scanner that can read in gm/* grams per second, then you'd convert to lb/m or pounds per minute.
To really know if the MAF is functioning correctly it is best to watch the hertz and see if when you accelerate, or decelerate, that is smoothly rises and decreases.

If you are talking about the MAP sensors signal wire voltage, then when you give it gas the pressure in the intake manifold should drop, and the voltage should rise, if not it sounds like your MAP sensor is bad.
If the MAP is not changing with the pressure changes of the intake manifold, then that could explain what I think your mechanic was referring to with saying MAF was showing in the negative, because that would cause it to lean out the fuel delivery a bit.

Before getting a new MAP sensor I'd be sure it is not a problem with the wire at the PCM.

As Dan said in that link ""If the reference wire (GRAY wire, pin 16 on PCM) is not supplying the specified voltage, check the voltage on this wire at the computer. If the voltage is within specifications at the computer, but low at the sensor, repair the reference wire. When this voltage is low at the computer, check the voltage supply wires and ground wires on the computer. If these wires are satisfactory, replace the computer.
""

I checked the MAF (not MAP) with this guide :
Part 1 -The Basics of Testing a MAF Sensor.
Yesterday i fix the ATF leak , i hope it'* help / solve the problem ...

Update : I fix the ATF leak , change filter and oil . I did a test drive today and after while the shifting start not goes smooth again .

The thing that makes me feel this voltage test for the MAF is inconclusive is that you say the reading stays at one value, and does not change at all, if this was the case the car would not accelerate or decelerate at all period.
I am not an electrical engineer, but I believe hertz is actually in an AC form, and when measured in DC it usually just shows 0, but I suppose it could just show one set reading at not change, since it cycles so quickly its variances cannot really be picked up as a DC voltage.
I am just going from things I have read, which I admit I do not totally understand, but in my research nowhere could I find that the hertz can be measured as a DC voltage, I am sure if you tested the MAF with a proper multimeter, set to display hertz, then you will see a variance in that frequency in relation to acceleration, and deceleration, I would not consider your MAF bad based on tests that site says are accurate.

Hopefully somebody with a better understanding of electricity, and hertz will post and provide better information than I have.
But until then I'd not waste money on a MAF thinking it is going to solve your problem.

Did you ever get MAF cleaner and clean the MAF like I suggested?

Did you ever test the MAP sensor?
As I said before, and as you should have read in the link to the writeup by Dan that I provided, a bad MAP could cause the problems you are describing, note that does not mean that is the problem, but it is a possibility, especially considering what you said about your mechanics comments in regards to your MAP sensor being negative..



If the fluid was not low when it was slipping this would not fix your problem, but having that leak fixed was something you needed to do regardless, and I am glad you got that problem taken care of.

you are right about testing the maf but i have never heard of a maf causing trans issues. tps maybe, but not long shift codes. i think that is something in the trans if not the dex cleaning type issues

All the things lead to the PCS , I need to open the side cover of the transmission , is not preventable .

Any advices before i do it ?
someone do it before ?
in generally is the steps to do it (correct me if i worng) :
1. remove the wheel
2. remove the brakes system
3. remove the cover around the wheel (plastic)
4. release the rack housing , steering wheel . (do i have to ?)
5. release the cradle , support it with jack
6. open the cover of the transmission

do i write ? i missing something ?

The PCS could be the culprit, but with what you've posted here about what your mechanic said about the MAF and MAP, I cannot see why you'd not test the MAP Sensor first, did you even read the link to Dan'* technical writeup?
Also the MAF could cause some similar problems if it is not functioning correctly, although I doubt that it is the MAF, I'd still have tested that the proper way.

The first thing is says in Dan'* Map Sensor writeup is below.

""Possible indications of a bad MAP sensor.
Late shifting or harsh shift, incorrect/rough idle, stalling, surging, lack of power.""

Another question, when i push(open) the throttle body and the RPM raise , if i do it quickly
i hear like a whistle from between the intake manifold to the throttle body .
i saw a space between them ...
that could be the reason to the hard shift that i got ?
recently i got some problems with the intake manifold and the EGR valve and i replaced them .