When you do a factory reset/data wipe, it does not put anything back from the stock firmware. When you install a new ROM, doing the reset just puts it in the "new" state for that ROM.
To restore back to stock, you will need to download the stock ROM for your device from SamFirmware (or another place if you know of one). Then you can use ODIN or Heimdall to restore the device back to its original state.
These are the steps that I took when I initially reverted my device back to stock (keep in mind this was about a year ago, so the files (version) used probably changed, but steps should be the same.
I couldn't give you downloads for everything because you did not say what device you have. Samsung made like 8 different versions of the Galaxy S.
You will need the USB drivers for your device if you don't have them installed
- Download ODIN
- Download 512 PIT
- Download JFD tar
- Note that all 3 of those are from the same thread. It also wouldn't hurt for your to read that post too.
Open Odin, plug in your phone, then put it into download mode.
- To expand on this because a lot of people were asking "how to put in download mode". The easiest way I found to actually do it, if you can can connect via ADB is to do the following:
# reboot download
If you can't get that to work, try how i mention below (phone off, battery out, hold vol+ & vol-), or try searching these forums for "vibrant download mode" you will find other things that "work" for people
load the PIT file in appropriate area.
- load the .tar file in the PDA area.
- DO NOT check 're-partition'.
- Click start, let it finish.
Hopefully ODIN doesn't fail for you here, but it did for me, dont panic
- At this point ODIN failed on me. and I got the "mobile-!-pc" image.
- Now, pull your battery and unplug USB
- I also took out the SIM and sdcard at this point.
- bring the phone to download mode again
- plug the USB back in (the phone should be off)
- Hold down vol+ & vol-
- Put battery back in
- press power
- re-run ODIN as mentioned above (if needed)