Ive been long time follower of this forum.I have read several time that water temp should not exceed 90dec. Yet when my car sitting almost idle in slow moving traffic sometimes the oil and water temps can reach upto 100+ deg (in 28deg cel weather)

once the car starts moving both temps fall to about 90.

is this normal behaviour or should I ask dealer to have a look?

 

Totally normal. On the run will never move much beyond 90C (water) even on the track. However if you are crawling in traffic it will hit 104-105 before the secondary fan comes on and knocks it down a bit. I was one of the first to notice this a year ago when I picked up my GT3 from Germany. I subsequently have talked with others and its the same across the globe.The warning message will come up when it gets to 120 and this will only happen when you have a problem (like failed thermostat). I had one of those too!