[Nexus 5 Original Android Development] ipdev:
Assuming you followed the steps and actually completed the (re)partition part.

You now have an 1.5G system partition and this will never change unless you manually partition the device again.

This is different than resizing an image.

If the rom installer does not include automatic resizing, you will be left with only the size the rom was built for. If it was built for a 1G system then, you will only have 1G available to use, .

Do a complete clean flash. (This will erase everything on the device.)

TWRP-> Advanced-> Wipe-> Format (Type Yes) enter.

TWRP-> Advanced-> Wipe-> Check all and Swipe to wipe

Reboot Recovery

Then install the rom

Mount system (either using TWRP or the command below.)

Check the size (use th df command below.)

- If you have 1.5G system then you are maxed out on space do to the rom.

- If you show 1G system size, then you need to expand the image to fill the partition.

To expand the system image, you can try using TWRP

Wipe-> Advanced Wipe-> (select System) Repair or Change File System-> Resize File System

This never worked well for me on hammerhead so, I also included the command below

System needs to be unmounted to run resize2fs

Good luck.

Sorry, some of us do not follow older/onetime use threads that well. :(

Just a suggestion, you could have mentioned 2020suite in your edit just incase he/she gave up on a repose from this thread and wasn't watching it.

No criticism.

As a community (we could do better) should still try to help others.

We were all juniors once. Thankfully it was a little different when I was and when I used the search function, I did not get overwhelmed by the same question being asked and repeated responses of use search. Either it was ignored, answered or pointed to a post the guided to the answer. (Now I hate searching on xda, the results in some threads are highly polluted.)

Please do not give up on helping, even if it's a little bit when you can.

Keep up the good fight :D

Did you format the partitions ?

TWRP-> Wipe-> Format Data (type yes) and tap enter

TWRP-> Wipe-> Advanced Wipe (Select all) Swipe to Wipe

TWRP-> Reboot-> Recovery

If you use fastboot to flash the images manually (boot, system, recovery) you can along as you wipe everything first and then wipe cache and data/factory reset in recovery and reboot.

It will not change anything as far as partitions but, you can run the last factory image this way if you want.

I assume you are using twrp-3.3.1-1_UA-hh

The vendor mount error is because without running the script to actually partition the device, you do not have a separate vendor partition.

If you use the regular TWRP and Format then wipe everything, do you still get an error?

I've done it three times now.

Factory to modified | Modified back to stock | Stock back to modified

I do not remember how I did it originally.

Might have pushed the zip to /tmp or /sideload and then used TWRP to install from there.

The last two times I just used adb sideload to run the zip and then TWRP-> Advanced-> Terminal (type the key word) to continue the dark magic.

I did it with the regular TWRP.

Don't need the vendor partition yet so, I'm not that worried about formatting and mounting it.

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A few commands.

Noted using adb shell.

If used in TWRP Terminal, ignore the adb shell part.

Mount system

adb shell sbin/mount system

Display file size (a=all mounted h=human readable)

adb shell df -ah

Unmount system

adb shell umount system

Resize system image on Nexus 5 Hammerhead

adb shell resize2fs -f /dev/block/mmcblk0p25

A few links that may help/explain.

The regular official TWRP.

Nexus 5 (Hammerhead) twrp.me - Link

adb/fastboot [Part of platform-tool]

SDK Platform Tools developer.android - Link

Post I made in a different thread that includes a quick explanation of partitioning and resizing images.

xdaThread [ROM][flo|deb][UNOFFICIAL][AospExtended-v7.0] - Link

Cheers all. :cowboy: