wifi takes 2 minutes to reconnect

Hi there guys. I have a Retina MBP 13 inch, late 2013, 2,4 GHz with El Capitan installed. Since I cleared the list of Wi-Fi, it takes me too long (app 2 minutes) to reconnect to my wifi. That happens at start-up, not after sleep, or when i join another (known) network.

What happens is the following: It takes too long to connect (app 2 minutes) and then I get the exclamation mark on the wifi symbol and a couple of seconds later, it connects normally and then i have no problem until I turn the MBP off and then on again.

I have tried:

1. Creating new "location" after deleting all networks that i had.

2. Clearing the NVRAM

3. Deleted the network preference files at /Library/Preferences/SystemConfiguration/

Does anyone else have the same problem?