- how many miles on x?
-ppi done at BMW or indy?
-are you certain they used BMW coolant w/ 50-50 mix distilled water?
-when they 'topped' off coolant was the key on and heater on low? did they follow proper procedure

if all are true, I agree with ed & rb probably a stuck open thermo... depending on mileage, you may as well replace it

__________________
'14 X1 7000 miles

Hasta luego a

'10 X3 3.0 55k miles
'09 335i 55k miles
'08 528i 94k miles
'09 Mini 88k miles
'06 X5 3.0 112k miles
'04 X5 3.0 128k miles
'99 528i 120k miles