what cause my 2004 Porsche Cayenne to overheat

Unless your coolant is so dirty that it is clogging up the system that is not the reason you are overheating. This could be a few things like a bad engine fan, thermostat, clogged radiator, bad water pump. All of these would need to be inspected by a qualified technician to diagnose the issue. If you don't work on your own cars here is a link to find a good shop near you, https://repairpal.com/repair-shops Alex