I don't know what or where SMCFan installs, but simply dragging the app to the trash may not have gotten everything and this may be why you are experiencing this problem. There are third party uninstallers like App Zapper and App Delete which will do this (you can google to find downloads), but you could also simply delete/move to trash everything that EasyFind finds and maybe this might be the safer option. EasyFind is freeware.
http://www.devon-technologies.com/products/freeware/index.html
Set it to search invisible files and in Settings to "Scan All Files"
I'd presume that SMCFan goes into some System/Library files (the fan.kexts) for its operation, and might have made some changes there, which is what you are experiencing. (And I'm not certain either, that simply removing the SMCFan stuff will restore those files (or file) to their original state.) This can be dangerous territory to muck about in. I'd only use the "Move to Trash" option (you'll need to authenticate with your password) so you can move something back if need be. And
only trash things whose names include SMCFan or Eidac (the name of the developer.) It's also possible EF won't allow you to move a system file to the trash. In that case, you'd have to locate it yourself and manually "Move to trash" after authenticating.
I would also repair the Drive and Permissions, in that order. You might need to Repair Permissions, since installing SMCFan, if it's installed deeply into the System, might have changed them. Repair Permissions from Disk Utility (Applications>Utilities) only when booted normally, not from the Install disk. Permissions Repair can take a very long time, up to an hour or more. Repairing the drive shouldn't take more than several minutes. And don't do Permissions Repair until and unless the drive checks out OK.
There are instructions here for Disk Repair.
http://support.apple.com/kb/TS1417
I'd also be sure to have a backup (something you should always have on hand, anyway) in case anything goes wrong.