Simple - tighten fanbelt.
Next.
Seriously (I am, sometimes) welcome to the Forum, good to see you've invested in the right model. Grab a torch, take a good look at the fanbelt. Check it for threads hanging out, chunks missing on the belt, etc., etc., Having no idea of your mechanical ability I won't say the tightening procedure is simple - for the unnitiated it can be a little daunting. However, Google is your friend . . .
Past-President, MR2 Owners Club Qld
"There is a fine line between hobby and obsession."