Would be helpful if you told us exactly which ECU it is by adding part numbers etc etc.

You may be able to read the 95040 eeprom with Argdub eeprom tool which you can find on here (if you cant read it in the car you will have to put the ecu into bootmode, again lots of info on here regarding this). You'll need the ftdi kkl cable to do this 232RL chip.

You can also read the stock file from the car and then use all of this data to clone an ecu to be the same as yours. stock file should be easy-ish to find on here/ on the internet but the eeprom read matters most as it contains your immo data. Look in the noob section and read all of the FAQ/stickies as well as the stickies related to flashing and bootmode.

 The most important thing is my ECU is chipped with custom map

 I want to keep all the custom map data otherwise I have to pay the extra money for the map

 Is it possible to do that?

Thx man

May i know can i do the O2 disble too ？

The "dumbest way" is a hot air station.
Replace the 29F800BB and the serial EEPROM on the new ECU with the ones on the old ECU physically.
The less dumb way is doing that in boot mode via software rather than desoldering.

yeah, I finally understand the whole meaning after the forth read

Just my understanding problem, not yours

your welcome
but as marty said earlier read and flash the 29f800 chip using bootmode, that would eliminate some potential problems during the process

its actually pretty "simple" to make a bench setup if you know how to read wiring diagrams and work with wire and electronics