Moto g not booting up.
I hope you have an unlocked boot loader.
The first thing you need to find out is that are your phone's partition writable and readable.
1. Download the latest CM11 nightly to your PC rename it to "CM.zip" and extract the contents to adb folder (adb folder should be in C drive i.e. C:/adb ). You will get boot. img , system (folder), and others.
1. connect your phone to PC in fastboot mode.
2.In adb type the below commands one by one without quotes. And let one command get processed before typing other.
"fastboot devices" (in response it must show you something like TJ9*****)
"fastboot erase userdata"
"fastboot erase cache"
"fastboot push C:/adb\system /system/"
"fastboot flash boot boot.img"
"fastboot flash recovery recovery.img"(flash the philz recovery now)
"fastboot push C:/adb\boot.img /data/"(to verify whether /data is writable or not)
"fastboot push C:/adb\boot.img /cache/"(to verify whether /cache is writable or not)
"fastboot push C:/adb\CM.zip /data/media/0/"(to push the CM11rom to sdcard to flash it through recovery)
Then boot your phone to recovery. And see the logs, it should show
/sd-ext error mounting /sd-ext
If it shows /data can't be mounted or error mounting /data. Then go to wipe and wipe /data and /sdcard and then again push CM.zip to /data/media/0/. If you don't see this error, then choose to wipe to install a new rom. After this remount /system /data /cache and flash the CM11.zip or you can flash stock firmware through mfastboot.
This method will definitely work since I, myself had this very same issue and got it resolved the very same way.
P.S. Try this method and only of you get some error then reply as I an sure it will solve your issue.
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