MBP Running slow when its on batteries .. working fine when plugged to the charger ?!

I am at the same point as the few reporting unexplicable CPU load after disconnecting the charger which leads to sluggish UI operation etc.. (MBP 13 early 2011, 2.3GHz)

Is this truely working? just wanting to confirm before I delete the file. I have a back-up just in case.

Thanks

Yodler, it worked for me and it also worked for Abhish. I haven't noticed any side effects from deleting the file, if you are worried back up the file so you copy it back.

Regards

Tony

Just an observation to alleviate my concern about the possible side-effect of removing this kext file

The original explanation what this file is designed to do i.e. running a low level task to a max to cool the CPU does not make sense because when my CPU is at 40 -50 Grad C 20 min after a boot the kernel file is already hogging cycles to slow down all other apps. The kernel cycle hog does its job at any temperature it seems ......

Thanks Although Is Was Scared To Do This It Worked!!!!

Thanks

Thank's a lot dear Tony_stead for this post,you saved me.The problem is solved now🙂🙂

Thanks alot for this post, helped me out alot I appreciate it!

Does reformatting the macbook help anyhow? I've done all of the things mentioned, but nothing seems to work for me...
My mac is a year old and occassionaly used. You never expect these kind of issues from a mac!

Monica, I reformatted the MacBook I was having problems with and it didn't make any difference.

Try it though, do a Time Machine backup first, format your disk and install a fresh system from the disks that came with your MacBook. Then restore from your Time Machine backup. If you still have the problem, try following my previous instructions exactly, step by step.

If that still doesn't work try upgrading to Mountain Lion via the App Store. As far as I know this only happens with Snow Leopard.

Monica, I have been to the Genius Bar in Stanford. All tests were done there and no problem found. When they told me that they would reload the OS X I took my MBP back home to perform another back-up (to be safe) and then proceeded to download the OS X from the Apple Server myself incl. reformatting the disk - which can take many hours. With just the newly installed OSX 10.7.3 running the problem re-surfaced with first just 50 to 60% System CPU and soon again up to 80% - our original problem. I then proceeded to load all user files from the back-up and of course the problem with sluggish performance while running on a healthy, fully charged battery continued - until I found and took out the kext file for my MBP type. Since then I am ok as new, monitored temperature und fan speed and for the last 2 months since the removal of the small file it runs fine.

Tony, Yodler, the kext file does not exist on my laptop. Reformatted the laptop last night, it's still the same. System CPU shoots upto 80% once the mains are unplugged. Is there ANYTHING else that I could do?

This happened to me on Mountain Lion. Deleting the file helped but the problem occured again after a week or so, deleting it again has helped so far...

Thank you very much. its working fine for me..

thanks buddy my macbook pro running fast now,after deleting taht file

Thanks a lot

Thanks a lot to tony_stead. Fixed my problem!

GENIUS!!!!!!!! THIS WORKED FOR ME !!!!!

😁🙂🙂🙂🙂🙂🙂

Try this at your own risk - It Worked for me after a complete system reload which didn't make any difference.

I will take no responsibility for any damage or loss caused to you or your property. Do it of your own free will and at your own risk.

I did this on a MacBook Pro Early 2011 - 2.7 GHz Intel Core i17

System Version 10.6.8 Snow Leopard

Running well on mains power but dramatically slowing down when running on battery power

First try this to see if you get the same result I got

Quit all programs

With the mains connected

Open Activity Monitor and click on CPU in the bottom half of the window

Check the CPU Usage graph - It will probably be minimal - Under 1%

Now disconnect the mains and watch the graph shoot up and CPU activity around 80%

Here's what I did...

Again - I will take no responsibility for any damage or loss caused to you or your property. Do it of your own free will and at your own risk.

Firstly, you’re going to need the model identifier of your Mac,

go to the Apple in the menu bar and select "About this Mac"

When the About this Mac pane appears click on "More info…"

Select Hardware in the left panel

In the right panel make a note of the Model Identifier e.g. "MacBookPro8,1"

Now open a finder window and click on Macintosh HD

Click on system >Library > Extentions

Find the kext file called IOPlatformPluginFamily.kext

Right click it and Show Package Contents

Click on contents

Click on Resources

Click on PlugIns

Right Click on ACPI_SMC_PlatformPlugin.kext

Right click it and Show Package Contents

Click on contents

Click on Resources

Find the the plist file that corresponds to your Model Identifier e.g. "MacBookPro8,1.plist"

Move it to the trash and delete it

Restart and everything should now be fine.