One problem related to engine and engine cooling has been reported for the 2005 Porsche Cayenne. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2005 Porsche Cayenne based on all problems reported for the 2005 Cayenne.
The engine has plastic coolant pipes between the front and back of the engine. They failed and dumped all the coolant out while on the road. Car was disabled and had to be towed. After researching, it's concluded that this is a very common failure in Cayennes with a v8 engine at about 60000 miles. Mine had 61000. This is a safety concern. The car can be disabled at anytime. Also, the repair is very costly, exceeding 3000 usd for parts and labor.