The first-generation Porsche Cayenne (Type 955 from 2002 to 2006, then facelift Type 957 from 2007 to 2010) is the model that saved Porsche from bankruptcy. Developed jointly with the Volkswagen Touareg and the Audi Q7 (PL71 platform), it shocked purists but enjoyed immense commercial success. The Diesel engine, the main focus of this report, was introduced very late, in 2009, on the phase 2 (957). It is the 3.0 V6 TDI block of Volkswagen/Audi origin. While the Cayenne I offers exceptional on-road and off-road performance, its overall reliability record is poor, weighed down by major design flaws on the petrol V8s (cooling tubes) and a fragile air suspension. Paradoxically, the late-career Diesel model is one of the most rational and reliable choices of this generation.
The first-generation Porsche Cayenne (955/957) is a double-edged sword. While its dynamic performance remains impressive, its reliability record is objectively poor, confirmed by ADAC and TÜV Report statistics (18.5% major defects). The phase 1 (955) petrol V8s are to be avoided unless the cooling tubes have been replaced with aluminum. The phase 2 (957) V8s suffer from fatal cylinder scratches. The case of the Diesel (3.0 V6 TDI 240 hp, 2009-2010): It is paradoxically the safest choice of this generation. Arriving at the end of the model's life, it benefits from a more reliable platform and a proven VW/Audi engine. It will nevertheless be necessary to monitor the anti-pollution peripherals (DPF, EGR) and the air suspension (frequent leaks after 80,000 km). To be purchased only with a complete maintenance history and a substantial reserve budget for electronic and pneumatic failures.