I have an old MacBook Air 13" from 2013. It has been working flawlessly up to maybe 6 months ago, where it started being insanely slow. I have identified the cause to be the dreaded kernel_task, that uses all my CPU.
The problem starts right after booting (maybe even during booting, it is very slow as well). The system CPU usage is constantly at 65-85%, where the free CPU can be 0.2-25%. The kernel_task is a 200-1000%. As it starts during booting, I don't believe it is actually high temperatures. Also the fan is very silent and the computer does not appear hot. There is no difference if I am on battery or power source. Ambient temperature is probably 21oC. When starting the Mac, I have to hold the start button until the apple logo appears, as it otherwise won't start.
What I have tried so far:
- Reset SMC
- Reset PRAM
- De-dust the macbook
- Update to the latest IOS
- Reset to factory settings and remove everything
- Deactivate turbo boost
What I have tried for screening the problem
- Run "sudo powermetrics --samplers smc" in terminal. CPU thermal level: 150. CPU die temperature: 50oC. Fan: 1200 RPM
- Run intel power gadget
Install Macs fan control and set to a high speed for a period, to cool the computer. Did not stop the kernel_task.
Boot in safe mode (still occurred).
Apple diagnostics only gave PPT002 "Battery functions normally, but the voltage is lower than when it was new"
What can I do to make my computer usable again? Resetting it did improve, as I before generally had <1% CPU available, but it is still not doing great.