One problem related to gas recirculation valve (egr valve) has been reported for the 2004 Porsche Cayenne. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2004 Porsche Cayenne based on all problems reported for the 2004 Cayenne.
Porsche knowingly manufactured Cayenne model vehicles with plastic coolant tubes that degrade and fracture causing engine coolant to leak into the engine, potentially leading to significant engine damage. Porsche has known about this defect and failed to make consumers aware of the potential failure despite the risk to the owner’s safety and pocketbook.