Mac running slow and fan running at high speed after water spill

I would open it up, remove the battery. Remove both RAM chips, then, one at a time, reinstall the RAM in each of the slots booting each time and checking the speed. This is to test both the slots and the RAM. Also try starting up from your system installation disk and check the speed to see if the hard drive could be adding to the problem.

The place to start is dealing with the liquid damage. If you don't have the residues from that cleaned up you are going to chase ghost and really can't actually determine if any parts are bad. Remove all power sources from your laptop. Push the power button for 10 seconds to help dissipate the capacitors. Then let it sit for an hour to ensure the capacitors have lost their charge. Next remove your motherboard and clean both sides of it 90% or better rubbing alcohol or distilled water and a tooth brush. All are obtainable from your Pharmacy. Be liberal with the distilled water or alcohol let it flow underneath the chips to wash away what is under them etc... Dry it off with paper towels and let it sit for a day to dry the parts you can't reach, like under ICs. You can use a hair dryer on no heat or a fan to expedite drying, but still let it sit over night. A guide for removing your motherboard is here. My background is electronics. I am not an Apple guru. Reassemble your laptop give it a try. If this didn't solve your problem do what mayer is asking you to do.

Removing the Webcam cable which also connects the wireless card fixed the issue for me. I would rather have an external wifi for now and get this going. Thanks for the advise.

I spilled water on my macbook pro today. Had similar issues - fan running at max and constantly from startup, my screen was flicking between dim and normal, one of the channels on my headphone jack was working at lower volume and the computer was running slow. I opened up the bottom, saw that there was some green corrosion on the motherboard, scrubbed that off with an old toothbrush and now it all seems to be back to normal.

Try Fan Control!

"Sorry to interrupt the post a little bit. Actually Mac OS X is good at of taking care of itself, if there are performance issues, there are a couple of things you can check:

Check your Login Items under System Preferences > Accounts to see what you have automatically launching.Also check /Library/LaunchAgents/ and /Users/yourusername/Library/LaunchAgents/ for items launching at startup

Launch Activity Monitor and change ""My Processes"" at the top to ""All Processes"". Then see what may be consuming your OS X system resources.

Check the System Memory tab at the bottom of Activity Monitor to see if you have excessive ""page outs"", a sign that you may benefit from more RAM.

Check if you are running any poor Mac anti-virus programs as they may take large resouces.

If you don't want to do these manually or the above check still won't help, let this Mac tuneup utility to perform a health check of your Mac and fix relevant issues easily.

Hope this help, best regards."