Sonoma 14 Mac book constant fan and overheating

EmD2511 wrote:

I updated my MacBook to Sonoma 14 a few days ago. Since that time the fan runs constantly even when nothing is open. The battery obviously dies much faster. In the activity monitor it says CMFSyncagent is 92.3% and remains at the top of the list far exceeding any other activity. I did the whole shut down, hold option/shift etc for 7 seconds thing. Once restarted this stops the fan for about 5 minutes. I don't have many downloads on my Mac. I have a ton of storage. I am blaming this on the update and not sure how to correct it.

CMFSyncAgent "Communications Filter Synchronization Agent" is a macOS System File.

If shutting down and restarting does not resolve your issue

A SafeBoot Use safe mode on your Mac - Apple Support will sort many anomalies.

Log in and test, reboot as normal and compare your results.