Iphone won't connect to Wi-Fi? - 2

I have an Iphone 4s. It doesn't have 3G on it because i now use the Iphone 5, so i use it as a sort of itouch. It only works on Wi-Fi. It use to connect to the Wi-Fi at my house fine but it started having problems. It won't connect to the Wi-Fi, sometimes won't even recognize it, and when it does, it only works for 5 minutes max. It connects perfect to my sisters and moms phone, so the modem isn't the problem. Every 10 minutes i restart network settings but it doesn't work at all. This is getting extreamly frustrating, please help.

I had an issue extremely similar to this with my 4s. What happened was that my internet was running slow, so i attempted to remove all of the wireless devices and restart the modem and router. For my iphone, i told it to "forget this connection" regarding the wireless network which i had established. After the reboot i reconnected all of the devices as well as my iphone which seemed to be working properly. The issue that stemmed from this was that my iphone now did not remember the password to my network and therefore did not connect automatically. In addition i had lost the feature to "forget" the wireless network. In an effort to resolve this issue, i did all the basic troubleshooting steps (reset network configuration settings, reboot the device, reboot the router, and removed the device from the routers range and reentered to attempt to reestablish the connection) besides returning my device to factory settings. When all that didn't work, i called apple care who further instructed me to restore my iphone to factory settings, establish it as a new phone and attempt to fix the connection before syncing my data. Still didn't work. My wife came home, looked at my phone went into Wi-Fi-> choose a network-> other-> and entered the name and the type of encryption, then the password and now it works fine, and the option to forget the network has returned.moral of the story… DUHH hope i help.