Normal behavior. The fan clutch is engaged at 100 or 105C and runs until 85 C, so the temp will oscillate between those two values.

Make sure the aux fan runs properly for good AC operation, and the engine fan will be inadequate in slow traffic.

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!