My friend has 56 plate 520d pre lci, his car temp gets to 97*C and that's when the fans kicks in but the fan switches off at 94/95*C. After driving about 2 miles in city traafic the temperature dropped to 78*c and then when stationary temperature is rising back to 98/99*c?! Any ideas? He has recently had the car remapped! Before remap he checked his temperature once or twice and he got approx 78-80*C after 15miles with speeds between 30-60mph. Any advice will be helpfull. Thx

 

Sounds to hot. Maybe its running lean after the remap

 

Defiantly sounds very hot.

 

All of the above, additionally the drop to 78 does not sound very healthy either. In my experience the 525d/530d/535d's, once warmed up, will remain within the range 85-90 unless you drive 'em hard and then suddenly hit city traffic. That will get the temps temporarily up to 95. Doubt it will be very different with the four cylinders.

 

The temps should always be at 88-93 unless the thermostats are shot (which I bet they are).
My temps were never going over 75c, after swap of both stats sits at a nice 90-92.