MacBook Air Sluggish and Loud Fan Noise

Please review the cursory description of the kernel_task process in If kernel_task is using a large percentage of your Mac CPU - Apple Support. I suspect you will find that it is monopolizing that Mac's CPU.

A runaway kernel_task can be due to a number of factors, such as:

• a failed or disconnected temperature sensor
• cooling system inefficiency (an inoperative exhaust fan on Macs so equipped, possibly clogged with dust, including the heat sink)
• a worn out, missing, or non-Apple (user-installed) battery on portable Macs
• similar hardware-specific causes including internal hardware additions or modifications, external USB and other connected devices, or the driver software required to use them.

Most of those problems are going to require authorized Apple service. Click Get Support to make an appointment.

Consider using Apple Diagnostics / Apple Hardware Test: How to use Apple Diagnostics on your Mac - Apple Support. It may or may not identify a specific fault. If it does you can bypass a lot of questions Apple may have, but even if it reports "no trouble found" you will still need to have them diagnose the problem.

Please get rid of "TotalAV". Those things are junk. Rule 1 of Macs is don't install junk.

Google Chrome will burden any Mac regardless of age or configuration in its mission to harvest your personal information:

https://chromeisbad.com/

https://contrachrome.com/

If you are required to use Google Chrome then I recommend that you buy a Chromebook.

Microsoft isn't distinguished by their ability to write efficient apps either. If you are required to use Microsoft products buy a Windows PC.

Despite both of those recommendations you might still prefer a Mac, but no Mac needs non-Apple "anti-virus" junk. Uninstall "TotalAV" according to its instructions. Same for "CleanMyMac". Do not install it, or anything like it, ever again.

Please determine if the same problems occur in "Safe Mode": How to use safe mode on your Mac - Apple Support

Hi!

This would more then likely be resolved by cleaning out your computer. Also sometimes the CPU paste could also use replacement especially if it's a few years old. The sluggish could also be software related. You may have to backup the system and complete reinstall. I suggest setting up as new and dragging over the info you need. Sometimes after a few years of software, they get bogged down and need a wipe. Typically some of the stuff I've mentioned will breath some life back into this computer but could also cause issues that are barely hanging on to surface such as hard drive sectors that have went bad.

Hope this helps!