[Q] [SOLVED] Wifi VERY slow after 4.4.2 flash!

Search This thread

htcdude486

Senior Member
Sep 4, 2010
59
14
Hope someone has some insight!

Thought I'd give Android 4.4.2 (KOT49H) a quick try earlier this week.

I was coming from a clean Cyanogenmod 10.2.1 install, before this I had flashed stock Android 4.3 (JWR66Y) for it's most up to date 4.3 bootloader/radio. Everything with CM 10.2.1 was working perfectly.

Whenever I flash a ROM I erase boot, cache, recovery, system, userdata first via fastboot.

Everything worked fine after flashing 4.2.2, enjoyed playing with it, wifi was absolutely fine at this point, but wanted to go back to CM 10.2.1 regardless.

Re-flashed Android 4.3 (JWR66Y) again so I got my bootloader and radio back (...I heard the KitKat versions don't play well with 4.3 roms)

Erased everything via fastboot again and reflashed back to a clean 10.2.1 install.

Now my wifi is CRAWLING 50kb a second when I try speed tests and play store downloads are unbearable!.

What I've tried...

CM 10.2.1, stock 4.2.2, stock 4.3

The only thing that 'fixes' wifi is going back to stock 4.4.2! What the hell happened? Any theories how something seems to have changed permanently since my KitKat flash?

You may say, why don't you just stay on 4.2.2, well, because I HATE not having the choice! I'm really keen to find out why I'm not seeing my normal wifi speeds on 4.3, what did it change?

I've searched, found ALOT of posts referring to wifi problems with KitKat, but not this one. Most of the fixes include changing my router settings. Obviously, my router was working brilliantly before so I don't think that is the issue.

(Sorry for the long question, any ideas would be appreciated!)
 
Last edited:

gravitysandwich

Senior Member
Jan 30, 2013
350
112
First of all why you want to be on 4.3????????? And probably because you have the new kitkat radio and bootloader and your using jellybean. Old ROM + new bootloader and radio DO NOT MATCH. Just reflash everything from the factory image from Google if you REALLY want 4.3. Fastboot format (partition). Then flash the imgs.


If you are on the old 4.3 radio and bootloader sorry for misreading. Js

Sent from my Nexus 4 using xda app-developers app
 

htcdude486

Senior Member
Sep 4, 2010
59
14
First of all why you want to be on 4.3????????? And probably because you have the new kitkat radio and bootloader and your using jellybean. Old ROM + new bootloader and radio DO NOT MATCH. Just reflash everything from the factory image from Google if you REALLY want 4.3. Fastboot format (partition). Then flash the imgs.


If you are on the old 4.3 radio and bootloader sorry for misreading. Js

Sent from my Nexus 4 using xda app-developers app

Well, I'd like to switch to CM 11 when it's released as a stable version, until then I'm very happy with CM 10.2 which is Jelly Bean.

I have re-flashed everything,

I'm running 4.3 with the correct bootloader/radio, thats whats crazy!

I'm using...

fastboot erase boot
fastboot erase cache
fastboot erase recovery
fastboot erase system
fastboot erase userdata

...to do a clean wipe! Am I missing something?

It just doesn't make sense to me why there would be a sudden change in my wifi?
 

htcdude486

Senior Member
Sep 4, 2010
59
14
OK, got it fixed and I'm back with full wifi speeds on CM 10.2.1 with bootloader and radio from 4.3 (JWR66Y).

Last time I ever...

fastboot erase boot
fastboot erase cache
fastboot erase recovery
fastboot erase system
fastboot erase userdata

After doing some reading I discovered there is no need for me to do this, so it may have been causing some problems.

Don't exactly understand the fix but here's how I solved it.



  • Flashed the images using the included script (./flash-all.sh - I'm on linux, I'm assuming you would use the flash-all.bat in Windows)

  • Booted up, connected to wifi, skipped signing into to Google

  • OTA update for 4.3 (JWR66Y) popped up, installed it.

  • Restarted - connected to wifi, signined into to Google this time. Went to the Play Store to test wifi download speed. Its fast again!

  • Rebooted to bootloader, insalled custom recovery and flashed CM 10.2.1, and I'm back in business, full wifi speed.


Hope this guides some people in the right direction, no need for such over the top 'cleaning' methods before clean ROM flashes I think is the lesson!