It wants to over heat.
 

So, this new 300SD of mine wants to overheat, though only at idle.. As soon as im moving the temp goes back down to around 80c. The moment I stop though, the temp starts to rise, (I just make sure im not stopped for very long). At first I suspected the fan clutch however, as I decended a long steep hill I decided to put the car in neutral. I was going 45 and the temps started to rise like when it does when im stopped..

Thermostat maybe?

Thanks for all your help

Aaron

crap.
are those expensive / hard to replace..?