high cpu usage even without apps running

Read Apps can affect Mac performance, battery runtime, temperature, and fan activity - Apple Support.

Please determine if the problems also occur in "Safe Mode":

• Safe Mode or "Safe Boot" is a troubleshooting mode that bypasses all third party system extensions and loads only required system components. Read about it: Starting up in Safe Mode
• You must disable FileVault before you can start your Mac in Safe Mode.
• Starting your Mac in Safe Mode will take longer than usual, graphics will not render smoothly, audio is disabled on some Macs, and some programs (iTunes for example) may not work at all.
• Merely starting your Mac in Safe Mode is not intended to resolve the problem, it's to observe its performance without certain additional components.
• To end Safe Mode restart your Mac normally. Shutdown will take longer as well.

Reply with your observations.

If the problem continues to persist reset the SMC. To learn how to do that read: Resetting the System Management Controller (SMC) on your Mac - Apple Support. Anecdotal reports also indicate an NVRAM reset may resolve the problem: How to Reset NVRAM on your Mac - Apple Support. Also, if FileVault is actively encrypting the startup disk, wait for it to finish.

Other causes for a runaway kernel_task may be a faulty hardware sensor. Those causes may be diagnosed using Apple Hardware Test, though only a report of a specific failure can be considered a conclusive result: Using Apple Hardware Test - Apple Support. If you cover the Mac with cases or "skins" while it's in use, including keyboard covers, don't. Any other obstructions to cooling efficiency should be avoided also. Read Mac notebooks: Operating temperature - Apple Support.

Uninstall "CleanMyMac3". Read below.

To remove CleanMyMac 3 itself, use its Uninstaller module, followed by these additional steps:

Remove the file ~/Library/LaunchAgents/com.macpaw.CleanMyMac3.Scheduler.plist

• To navigate to that file, copy and paste the following line into the Finder's Go menu > Go To Folder...

~/Library/LaunchAgents/

com.macpaw.CleanMyMac3.Scheduler.plist

• Then, open  (Apple menu) > System Preferences > Users & Groups > Login Items.
• Select the item CleanMyMac3 Menu
• Click the [—] (minus) button.
• Restart your Mac.

Beware that reinstalling OS X alone will have no effect on either removing CleanMyMac or reversing the damage it is capable of inflicting upon a system. To recover from the effects of having used it to modify OS X, the additional software you require and the essential files you need, follow the applicable recovery procedure below:

• If you have a backup that you created prior to using CleanMyMac, now is the time to use it. For Time Machine, boot OS X Recovery, and at the Mac OS X Utilities screen, choose Restore from Time Machine Backup. Choose a date preceding the installation of CleanMyMac.
• If you do not have a backup that predates the use of CleanMyMac, create one now. To do that read Use Time Machine to back up or restore your Mac.
  • The recovery procedure will require that you erase the Mac using OS X Recovery, and then create a new User Account whose contents will be empty. You will then be able to use Setup Assistant to migrate your essential documents including photos, music, work products and other essential files.
  • To erase and install OS X read How to reinstall OS X on your Mac.
    • Follow the instructions in that document under Erase your drive and install OS X.
    • Then, follow the procedure in Move your content to a new Mac.
    • When asked how you want to transfer your information, select Transfer from a Mac, Time Machine backup, or startup disk.
    • Under Select the Information to Transfer, select only your previous User account and do not select "Applications", "Computer and Network Settings" or "Other files and folders". De-select those choices.
  • Subsequent to using Setup Assistant, you will need to reinstall the essential software you may require, once again remembering to install software only from their original sources, and omitting all non-essential software.
  • "Non-essential software" is a broad category that includes but is not limited to third party "cleaning", "maintenance", and "anti-virus" products.

Good morning Brookeboh, and welcome.

Please start your own new thread. Many experienced helpers here ignore what are called "threadjacks," especially of very old threads. Too hard to manage the information when multiple people are asking questions in the same thread---someone usually ends up getting the wrong information. Also, "exact same issue" seldom proves to be the case.

When you repost be sure to include a full description of your MacBook Pro including the all-important sub-model (Ex: "13-inch Mid 2012") and the Mac OS version it is running. Both are available by choosing "About this Mac" from your "Apple" menu (left end of menubar. For example, mine looks like this:

I look forward to seeing your post.

The bar graph shows mostly red, indicating that system processes (rather than user processes) are using most of the CPU. Select "System Processes" (or "All Processes") in the "View" menu to see which system processes are involved. That should make the job of determining why it is happening easier. Let us know what you find out.

If we can rule out third-party software (since you didn't install any), you should consider the possibility that the high kernel CPU is being caused by some recurring hardware error being handled by the kernel. Try running Apple Hardware Test or similar test suite.

It was nice and clean

Ummm, I don't think so.

In the second screenshot Clean My Mac 3 is running. It is a third-party product whose usual outcome is poor performance. I doubt we can help much further until that program is removed--it could be hiding other issues.

Hi Haematinon,

Did your issue ever get fixed? If so, can you advise what you did to fix it. I am facing the exact same issue, high cpu usage by system in the 70-80% range with Kernal Task the culprit.

Thanks

mvp4pres

Hi John,

Appreciate this thread is super old, but on the off chance you see this, I had the exact same issue, however when opening in safe mode the problem went away. Any ideas what that could mean or how I could resolve it? Thanks :)

What did you do to fix this issue?

Im experiencing exactly the same thing. The CPU is around 80% usage but not software is opened. What causes this?

Anybody who can answer me please? Im really desperate :(

If you are desperate, read the previous posts about tagging onto old threads causing delays in getting help and start you own thread. Provide all the tech details available about your model, sub-model and OS version.

Me to. I think it's the new software update. I just installed it a few days ago and today my mac became really slow. I went to the system activity and my kernel_task was at 130%.

I think we just need to wait for the next update....

hey there! i don't think so... sometimes it works correctly and sometimes this issues appears.

What i have tried is turn my Mac on in safe mode and this way the computer works correctly, although you are going to have the sound disabled. But at least it will work correctly.

Good luck

When you viewing Activity Monitor, switch to All Processes as opposed to My Processes. The system is using a very high percentage of the CPU.

Thanks so much Allen, much appreciate the advise, as i'm sure you can see i'm very new to all this and not a techy at all!

Ticket here if you wanted to see CPU usage super high but no apps running 🙂

You said you "decided to simply format everything and proceed with a new, clean system." Was it still nice and clean when you took those screen shots, or had you reinstalled any non-system software?