THE SUPER-SUV
For the 2003 model year, the Cayenne landed to mixed reception, but the introduction of a high-output turbocharged variant soon turned frowns upside down…
For many decades, Porsche’s publicity machine has been one of the slickest in the business, yet it curiously failed to deliver when the carmaker’s first sport utility vehicle (SUV), the original Cayenne, was sensationally unveiled to coincide with the 2002 Geneva Motor Show. Event photographs showing one of the most significant new Porsches ever assembled caused global jaw dropping as enthusiasts struggled to take in what they thought they saw: a dumpy, highwaisted estate car with styling that could have been the work of a mainstream manufacturer. A real Porsche, they argued, could be nothing other than a sleek sports coupe or convertible with no more than two-plus-two seating and ground clearance set with manhole covers, not boulders, in mind. There seemed a risk that building an SUV would, long term, devalue the brand which had been carefully nurtured for more than fifty years.
We now know, of course, the Cayenne was a huge success. Porsche planned to build 25k units per year, but within three months of the debut, the order bank stood at 87k, with talk of a three-year waiting list. Within that time, the Cayenne became Porsche’s top seller and, twelve years later, would spawn another hit for Porsche, the Macan crossover SUV.
There were initially two Cayenne models, the Cayenne S having a 4.5litre V8 producing 340bhp and 310lb-ft torque, while the Turbo’s version of the same unit gave 450bhp and 457lb-ft. Volkswagen’s equivalent SUV, the Touareg, had less powerful engines in the form of a 3.2-litre V6 and 4.2-litre V8, plus a 2.5-litre V6 turbodiesel. Notably, the Cayenne was Porsche’s first V8-engined product since discontinuation of the 928, the brand’s first off-roader since its tractor range (manufactured during the post-war years) and, perhaps most controversial of all, Porsche’s first vehicle with — shock, horror — four doors.
Though the Cayenne line thus far is generally considered to be split by two
different generations (9PA E1 chassis from 2002-2010 and 92A E2 chassis from 2011), the initial 955 model was superseded by the 957 for the 2008 model year. Increased displacement (4.8 litres) upped the ante, resulting in engine output of 486bhp and 516lb-ft. It’s this model on the pages before you.
Much like 996 and early 997-generation 911s, the first-gen Cayenne has a reputation for cylinder bore wear. It’s a rare occurrence, hugely amplified by online reports from those unlucky enough to have suffered engine failure as a consequence of the problem. A noticeable knocking noise from the front end will tell you if there’s cause for concern, which amounts to a complete engine rebuild or, best case, the installation of a donor engine. Walk away from any Cayenne you suspect is being propelled by a busted lump. Thankfully, Turbos feature under-piston oil squirters which pretty much negate the risk of damage, but make sure you listen carefully when the engine is operating under load and at idle before agreeing to buy the SUV that’s caught your eye.
KEEP YOUR COOL
The low cost of an early Cayenne Turbo (early 4.5-litre examples are available for less than the cost of a 924 S, while facelift models can be bought for ten grand) is very appealing, but approach with caution. “The biggest concern is the V8’s cooling system,” says Gary Conway, founder of London-based premium marque tuning and maintenance specialist, GCAP Performance. “Early Cayenne Turbos feature plastic coolant pipes, which send fluid to the turbochargers, as well as to the engine itself. These pipes become brittle with age. Facelift models feature aluminium parts, but a small number of early 957 Turbos managed to roll off the production line with the troublesome plastic pipes in place. It’s essential buyers check the condition of these pipes on any prospective purchase.”
He goes on to explain how Cayenne header tanks can also split over time (“they’re VW expansion tanks in a superhot Porsche engine bay”) and how coolant loss can be experienced by the crossover pipe between heads at the
rear of the engine. “It’s crudely glued into place. The adhesive softens, resulting in a loss of fluid. Porsche redesigned the coolant manifold to cure the problem, but it’s an expensive part to buy from main dealers. Some owners bodge the fix with a grub screw. In contrast, GCAP offers a well-designed, two-part screw-in pipe which eliminates any risk of failure and is significantly cheaper than buying a new manifold from Porsche.”
FLUID THINKING
Oil changes should be observed every five-thousand miles and, though Porsche claims timing chains last the life of the V8, Gary recommends not letting the host Turbo run on its original chain kit for more than 100k miles. While either of the Turbo’s V8s (the 955’s 4.5 or the 957’s 4.8-litre unit) require little maintenance other than an oil change every five-thousand miles, the ancillary systems can prove problematic. The wide-mouth front bumper, for example, is a magnet for leaves, small stones and a general build-up of dirt, meaning it’s the primary cause of damage applied to the radiator, air-conditioning radiators and intercoolers. “If the car you’re looking at doesn’t have functioning air-conditioning, have a look at the radiators up-front before assuming a gas recharge is all that’s required,” Gary advises.
The Cayenne Turbo’s fourby setup can produce a worrying error message if the traction control system believes it has a detected a faulty transfer box servo motor. Before you panic, consider the health of the host vehicle’s battery. Weak units can cause all sorts of problems, from alarm activation to random dashboard messages. If the battery is fine, of course, you’ll probably need to buy a new servo motor. The part when bought from Porsche is expensive, but consider the fact the first-gen Cayenne is based on the Volkswagen PL71 platform, shared with the VW Touareg and Audi Q7. This means many of the Porsche’s parts are available under a different part number for VW use at much lower price. Thankfully, replacement of the servo motor is a straightforward job.