My 1989 750il shows temperature just over 1/2 on guage at driving speeds - even in the summer. BUT,when idling in traffic,temperature climbs up to the red zone. (Of course I don't continue to run it at high temperature - I turn it off,get out of traffic,or something!) I live in Las Vegas,Nevada and need to cure this problem before summer. I have already replaced the sensors and thermostat. The second electric fan is working. I haven't replaced the radiator. Any suggestions on how to improve cooling at idle? Ways to improve air flow to engine compartment? Will appreciate advice. Thanks- George