Kernel task, high CPU 500%

Hey community,

I have MBA mid 2012 13inch, i5' 128SSD, osx yosemite 10.10.4 (if I remeber correctly)

It started randomly and boot up was super slow with high fan speed, so I force shut it, did SMC and PRAM resets, but still nothing. Had to wait 5minutes for it to boot up, everything was super chopy and laggy with high speed fan, but managed to get into activity monitor and spot that kernel task is killing it with incredible 300+% CPU usage.

googled and found out that this method worked for many people.I had the same issue 2-3months ago which I solved pretty quickly, by using the aame method.

1. Go to About this mac under the apple in the upper left and click on More info

2. Click on system report

3. make a note of what it says after Model Identifier

4. go to your master drive – System -Library – Extensions – IOPlatformPluginFamily.kext -Contents – Plugins – ACPI_SMC_PlatformPlugin.kext – Contents – Resources – find the name from step 3 and move it to a folder that you can find again if needed.

5. Restart and you’re done

BUt this time it was different, after trying to go to the folder there I have to delete the file with my model identifier, I found it totally empty and couldnt do a thing.

i Have a bachelor defence in couple weeks and **** loads of info which wasnt backed by time machine.

Any suggestions how to solve it?

Thanks.