I understand your dilemma. I used to own the Motorola Triumph that had such poorly written gps files, that it took five minutes to lock, if ever! A great dev on XDA Developers website wrote a patch fix for the problem. Look for..
AGPS PATCH FIX on that website, and read thru it thoroughly! Then download Faster GPS by Sufficiently Secure from Google Play. It will allow you to make changes to your gps library. I recommend just choosing your continent & region if you can't find any info for your carrier & manufacturer. Those settings are device & network specific so be careful. Faster GPS will allow you to revert back to original, but I still recommend caution. Once you've made your changes, reboot your phone. It helps make the settings "stick". It works! I live in the mountains and I get Google Maps loaded in 2-3 seconds on my little LG F3. I'm on Virgin Mobile. Nice! Good luck!