Here you can find complete Guideline of How to Flash a Stock Firmware in LeEco Letv Device you Need to Follow All Below Content Steps for Installation of LeEco Rom.
How to Install LeEco Stock ROM Method 1: Through File manager
Step 1. Download the multilingual EUI Latest Available ROM.
Step 2. Rename the Downloaded zip file as update.zip, and copy it to the root directory of your Device Internal storage.
Step 3. Open the Phone “File Manager” and click the firmware “update.zip” to upgrade Phone firmware. Click “Update” Option.
Method 2: Upgrade Through Phone Recovery Mode.
Step 1. Transfer firmware “update.zip” to the root directory of the Device SD card.
Step 2. Power off your device, Press the Volume up key and the Power button at the exact same time, wait until the phone screen wakes, it will enter into the device recovery mode. (You can also boot into stock recovery mode by Going into Settings Option> System Updates > Tap on the dotted button at the top and click on “Reboot into recovery”)
Step 3. Finally, click on “Updates system” & select the downloaded zip file. Wait for the upgrade is complete, reboot into the system.