Fan noise on startup for at least 5 minutes
Every day when I'm starting working on my laptop, fan (I think it's left fan) is noising for at least 5 minutes. After that it's working quietly.
I've recorded the noise, you can listen it here https://soundcloud.com/pavlentij/macbook...
Should I replace the fan or it can be fixed with oil? If it's not fixable then how I can discover which one fan is noising?
I would not put oil on a fan. The fans can be replaced (study the guide and comments before doing so).
A fan app will tell you which fan is running at high speed.
Perhaps all you need to do is clean off some dust. I would (try that first). After you've cleaned the inside you do not have to completely reassemble the machine to test it and see if the problem was solved...
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