BMW: desperate with my bmw, coolant system, fan clutch

Question
Josh,
how are you,
I have been desperated w/my car. I have a 2000 328i and the car has been broken around 6 times last month. The latest is the car starting heating up slowly until one point that i cannot drive. have to wait for cool again. last week the repair shop changed the expasion tank and the coolant for the car. Everything looked ok untill the car starts heating. Now nobody find the problem even the dealer. I saw that you wrote something about flushing the coolant system. It may cause the problem?woul you have sugestion,,,thanks very much  jean

Answer
Jean,
 The only way the coolant would be the problem, is if there is air trapped in the system from when the coolant was changed.  Have your mechanic's checked the thermostat?  That is the usual suspect in overheating issues.  Also make sure your fan clutch is working properly, a worn one will cause over heating
 Hope this helps,
 Josh