Kernel CPU usage ad 250% on Idle MacBook Pro 13"

Question

I recently (August 2011) purchased a MacBook Pro 13", 4 GB Ram, Intel i5, 320GB HDD. This is my first MAC and I was pretty excited.
However after using it for a few months one issue is constantly bothering me.
When I start up my MAC the fan starts making loud noises. This happens 75% of the time. AT first I thought that it would go away and went aboyt my work. Slowly I realized the the MAC was actually very slow and the fan noise never subsided. When it does the MAC works like a charm.
I checked the memory usage in the Activity Monitor and found it to be healthy. At this moment with a Browser (chrome) and Finder opened it has 2.6 GB of free memory. However the CPU usage is very surprising. Just one process, which is teh kernel task is hogging everything and is at 250% consistently. WHen it does come down (sometimes when I am lucky) the fan noise also subsides.
Has anyone faced this issue? Or am I just one of those unlucky people who got a bad MAC.
Any help/pointers etc appreciated. I dont want to be disappointed with my MAC experience.
Thanks

Answer 1

Please read this whole message before doing anything.
This procedure is a diagnostic test. It won’t solve your problem. Don’t be disappointed when you find that nothing has changed after you complete it.
Third-party system modifications are a common cause of usability problems. By a “system modification,” I mean software that affects the operation of other software -- potentially for the worse. The following procedure will help identify which such modifications you've installed. Don’t be alarmed by the complexity of these instructions -- they’re easy to carry out and won’t change anything on your Mac.
These steps are to be taken while booted in “normal” mode, not in safe mode. If you’re now running in safe mode, reboot as usual before continuing.
Below are four lines of text in monospaced type, which are UNIX shell commands. They’re harmless, but they must be entered exactly as given in order to work. If you have doubts about the safety of running these commands, search this site for other discussions in which they’ve been used without any report of ill effects.
Some of the commands will line-wrap in your browser, but each one is really just a single long line, all of which must be selected. You can accomplish this easily by triple-clicking anywhere in the line. The whole line will highlight, and you can then either copy or drag it. The headings “Step 1” and so on are not part of the commands.
Note: If you have more than one user account, Step 2 must be taken as an administrator. Ordinarily that would be the user created automatically when you booted the system for the first time. The other steps should be taken as the user who has the problem, if different. Most personal Macs have only one user, and in that case this paragraph doesn’t apply.
To begin, launch the Terminal application; e.g., by entering the first few letters of its name in a Spotlight search. A text window will open with a line already in it, ending either in a dollar sign (“$”) or a percent sign (“%”). If you get the percent sign, enter “sh” and press return. You should then get a new line ending in a dollar sign.
Step 1
Copy or drag -- do not type -- the line below into the Terminal window, then press return:
kextstat -kl | awk ' !/com\.apple/ { print $6 $7 } '
Post the lines of output (if any) that appear below what you just entered (the text, please, not a screenshot.)
Step 2
Repeat with this line:
sudo launchctl list | sed 1d | awk ' !/0x|apple|com\.vix|edu\.|org\./ { print $3 } '
This time, you'll be prompted for your login password, which won't be displayed when you type it. You may get a one-time warning not to screw up. You don't need to post the warning.
Step 3
launchctl list | sed 1d | awk ' !/0x|apple|edu\.|org\./ { print $3 } '
Step 4
ls -1A {,/}Library/{Ad,Compon,Ex,Fram,In,La,Mail/Bu,P*P,Priv,Qu,Scripti,Servi,Sta}* 2> /dev/null
Important: If you synchronize with a MobileMe account, your me.com email address may appear in the output of the above command. If so, change it to something like “[email protected]” before posting.
Remember, steps 1-4 are all drag-and-drop or copy-and-paste, whichever you prefer -- no typing, except your password.
You can then quit Terminal.