How to solve my iPhone 4s Wi-Fi problem once and for all?

My Wi-Fi was grayed out one week ago. (my iPhone runs ios7.1.1 now) so I looked up on the internet for a solution. The first thing I did was to restart it, but it did not worked, so I tried the one with freezer and surprisingly the Wi-Fi problem was fixed, until the next day… So yesterday I restarted it again and It worked and NOW Its greyed out again. I need a solution that will work 100%.

Saw that freezer trick too. It's a hardware issue listed in one of these below. Sounds like a repair soon. Find a local phone shop or attempt to repair yourself.
Best luck.

http://support.apple.com/.../kb/ts1559

http://www.ifixit.com/...reyed+out)

https://discussions.apple.com/...4?tstart=0