Mini R53 ori file changes when read out multiple times

I have a mini R53 in my shop at the moment and we are looking to make some mild changes to the map to hopefully get it running a little closer to normal. 

On reading the file a few weeks ago i noticed that the file would have some changes at the beginning every time the ecu was read out , sometimes there are quite a few changes and sometimes they are closer to each other. Having not been near a mini before i am hesitant to load a file on with these changes taking place. Hoping someone can enlighten me a little on if i should be worrying so much as i cant seem to find any information on this subject on here ( feel free to point me to a thread if i'm being stupid ! ) 


The car in question Is a JCW variant from 2004 ,  the last 4 reads we made of the car are attached to this thread. Any help would be greatly appreciated, we have the car now mechanically sound so it would be nice to get on top of the tune too

Post ecu type.

If is a siemens it haven't eeprom so use flash for live data, and is normal that every readed file is different.

The ECU seems to be EMS2k - 740A04003EWS1 is the software number i get from it.

The last time i read out the file file FFFFFF4 , this file appears to me to have the most data in it , the second read FFFF2 seems to have the most missing .

File was read with genuine Mpps and Data area only but it seems to read the full 512Kb every time.

Is it really normal for the mini ECU to read out this different each time on the same car , smallest difference is around 2000 bytes , largest ( most strange one ) seems to be 12000 bytes , all read from the same car just back to back reading to check that nothing weird is going on

can be checksum variations , too , right?

easiest thing to do is post the files or screen shots of the differences

if you read a file once and then read again straight afterwards (not starting car etc) are those files the same?

Yes , ok understood ,

First file the car gave out , the car was started and run after this file was read ,

the last three files the car was not started , only IGN cycled on and off after reading and still we have quite a lot of changes. I will try to make some screen shots of the differences. Smallest differences between the files is just under 2000 Bytes which seems quite a lot to me

Ok so after more testing , reading with the kess , it seems to miss the whole first area / 75% of the file so its only looking at the map data only area. If i were to load back on with the kess i would assume it will only write the data only.

With the MPPS , even with data only selected it seems to pull out a lot more with the first portions varying slightly, i am them assuming it maybe only writes the actual map data area when loading up a file. Feels safer using the kess as id rather not load back on a weird varying file even though it may actually be totally safe still. Ok ideal ish

I was hoping to use the MPPS checksum after making changes but possibly paying EVC may be safer ?


* updated , Used a genuine Kess V2 , first portion of the file ignored and map data only write. Checksum with EVC tested and working good , car just needs tuning now ..........

if you have kess just use kess. no checksum required.