Any way to narrow down whats causing kernel_task to use 100% cpu?

[thesuffering]

Laptop details: Dell Inspiron N4110 - Intel Core i7-2640m - Series 6 - HM67 chipset - 6GB DDR3 - HD3000 1366x768- Realtek RTL8105 Ethernet - NEC/Renesas USB 3.0 - Azureware Broadcom BCM94352HMB wifi/bluetooth - Clover UEFI

 

10.11.6

 

Have both a Yosemite and El Capitan partition computer on the same HDD until I can get El Capitan working right and can move on from Yosemite.  El Capitan has a large lag to it, and after messing with it, it appears kernel_task is pegging 100% of the CPU at all times.  Beyond the lag, the rest of it is running pretty solid.  Ive been told its likely a kext that is probably locked up in an endless loop, and the only way to isolate it is a process of elimination.

 

The only kexts ive installed myself are:

 

USB Stick:

FakeSMC.kext

GenericUSBXHCI.kext

USBInjectAll.kext

VoodooPS2Controller.kext

 

HDD:

FakePCIID.kext

FakePCIID_Broadcom_WiFi.kext

AppleHDA.kext (patched for ALC269)

 

I havent moved the clover install from the USB Stick to the HDD yet, as I want to get everything working right before migrating it as the clover install on the HDD seems to be fine for the yosemite partition.

 

Beyond the kexts, Ive put in a SSDT for power management, and modified DSDT for brightness control, battery (which isnt working still) and for AppleHDA.

 

I highly doubt any of the kexts on HDD or DSDT, SSDT edits have anything to do with it, as the lag was there from the initial install.

 

If I can get the lag sorted out, thats the only thing really keeping me from going ahead and switching completely from 10.10 to 10.11.  The rest is minor, manageable stuff.

 

Any thoughts on where to start or at least sniff around to figure out why kernal_task is 100% cpu?

 

 

[thesuffering]

This was resolved thanks to help from Rehabman.  Turns out I was fighting the wrong battle.  I thought my USB3 ports were Renesas, but it turns out they were Frisco Logic FL1009, and this was playing havoc on kernal_task (and on boot, there were lots of usb errors).

 

The fix was to remove GenericUSBXHCI.kext, and install a port injector from Rehabman.  Google kext injector + fl1009 + rehabman, and it should be the first result on google, 2nd post on the link.  

 

This fixed the problem right away.