Chosen Solution

I’ve been struggling with this kernel_task issue. I Looked for all information that I could find on Google and did not pay much attention to something on a document that suggested non original hardware installed. I realized that even though my battery seemed working working fine, it was not from the fruit brand (trying to avoid your anti spam robot guys). I’ve been monitoring all sensors that iStats could provide for my machine and worried about GPU Dies and wireless controller IC showing a dash or a low weird value but, the thing that did the trick was to simply unplug the battery and run it on power adapter. Each machine may behave in different ways but maybe you forgot that your battery was replaced by a “compatible” long time ago that happens not to be so compatible with High Sierra anymore unless you delete the plist file many documents that can be found about this issue… May this experience be of any help to others. Update (07/06/2018) Hello Dan! Thank you for your answer. In brief, installed OS High Sierra from Scratch, erasing HDD first. The situation was: starting the system will be fine till random times from 5 min to 1 hour when kernel_task started eating CPU up to 100% making system unusable, very slow cursor, etc. specially running on battery power. More stable but still it may happen when charging. In safe mode seemed okay. Weird sensor values I mean low GPU Die Analog temperature on both integrated and discreet GPUs. Reading up to 50°C when running Heaven Benchmark. GPU Die digital will stay “-” and Wireless Controller IC as well. Close the lid, leave it closed a few minutes, open it again and got some 5 or 10 minutes normal operation. All temperature values normal between 25°C (battery) and up to 80°C CPU (average 41). Changed thermal compound CPU and GPUs Arctic MX4. Disassembly main board and cleaned with printed circuit cleaner including connectors. Did shift+ctrl+option power for 10 seconds or more and cleared NVRAM. One week with this situation after clean High Sierra installation. I’ve been working with it the whole day without battery without any problems so far. Reconnected and changing battery while posting and capturing screen shots and running for more than one hour without issues so far. What did the trick I dunno but I will keep testing… Thank you once again and best regards from Spain! PD: Sorry for the typos, this Mac has an AZERTY French keyboard I don’t get used to and I’ve been told hard to change because that would mean tearing the whole thing appart… ;D (saw already the tutorial)

Your battery has no direct bearing on your CPU’s kernel Task. There is nothing going on with batteries in MacBooks with High Sierra where you needed to delete the plist file. Be careful of your sources! Some info is way off the mark! More likely the update process hadn’t finished re-indexing the drive. If your drive is quite large and full it can take a bit of time and this is done in background you would need to review the running processes to lock down what process is chewing your CPU’s cycles! I would also make sure you’ve maintained your OS & apps making sure they are up to date. Your battery is directly wired to the SMC chip. The SMC chip could have a bearing on your processors clocking when it goes into thermal fail safe or one of the sensors is misbehaving. You would have very different symptoms in that case. The source of your battery is important! Not every maker and seller do their homework. Basically, you get what you paid for on the most part. You talk about having odd measures within iSTAT are you using the correct version for your OS? How about taking a screenshot of iSTAT where you have questions on, past it here so we can see it Adding images to an existing question I’m sure we can get you straightened out.

Hi Alberto, i know that one year has gone but i hope you’ll read this because i’m in trouble with this kernel_task and would like to text with you if you’re available. Dave

Thank Alberto. The problem is that i don’t know if the battery is original or not because i’ve bought it used from subito (your name is italian i hope you know “subito”). Yesterday i took my Macbook late 2013 from apple store after 3 test days and they say to me everything works fine, but i still have the problem, i stupidly forgot to ask them if the battery is original. By the way, i was reading from your post maybe there is a file to modify for High Sierra when the battery isn’t original. Which file? Is it the same path in Catalina? “in both of my cases, replacing the battery with a OWC NuPower Newertech did the trick.” “OWC NuPower Newertech” is a brand of battery? Are you suggesting to change the battery also if it is still original? Thank you very much, i think you had the same problem as mine.

Old thread, but I am having a similar issue. After installing an OWC NuPower battery in my 2015 MBP the kernel task goes nuts (490% of CPU) and the system is barely operable when connected to power. As soon as power is disconnected the kernel task goes back down to normal and the system becomes operable again. I have reset the SMC and it did not help. Any ideas?

I’ve seen this a number of times, across various models. As strange as it seems, in my experience this is often a battery issue and a replacement - be it OEM or third-party - can fix this otherwise hard to nail-down issue. In cases like this where you experience inexplicably high kernel_task usage, disconnect the battery and (assuming your p/s provides enough juice) you should be able to boot-up and see if the high cpu usage continues to be an issue or not. If not, replace the battery and (all going well) your issue will be a thing of the past.