Continuing a relationship between Porsche and Volkswagen that goes back to the first Beetle, the 2011 Porsche Cayenne S Hybrid shares a lot of DNA with the Volkswagen Touareg Hybrid, perhaps too much. The cars are built on the same platform, and get the same hybrid power train. The Cayenne S Hybrid looks like a Porsche, but is it different enough from the Volkswagen?
Two areas where the cars differ are suspension technology and cabin electronics, but the Porsche doesn't win in both categories. You would expect a Porsche, even a Cayenne Hybrid, to have superior handling, and it does, feeling light on its wheels as it slips through corners like a dancer.
But despite luxury cabin appointments such as a leather-wrapped dashboard, the Cayenne Hybrid's electronics are somewhat mixed, lacking a unified Porsche identity and seeming shoehorned into the dashboard. Porsche's reliance on Volkswagen for its navigation software further obscures the distinction between the two cars.
Maintaining a quiet elegance, the Cayenne Hybrid takes no great pains to advertise green-ness. The only indication of its electrification is a small hybrid badge, in cursive Porsche script, adorning the fenders. The back of the car proclaims something much different, sporting big, dual tailpipes.
Those style cues point out that the hybrid system in this car is really more about achieving power, with only a modicum of extra fuel economy. The EPA rates the Cayenne Hybrid at 20 mpg city and 24 mpg highway, not dramatically high numbers, although a decent step up from its brethren, which show city numbers in the midteens. In a course of city, freeway, and mountain driving, CNET's review car turned in a solid 21 mpg.
That sort of mileage isn't bad, considering the Cayenne Hybrid's power. Porsche slips an S into its model name, which is wholly deserved. The 3-liter direct injection, supercharged V-6, combined with the electric motor, push horsepower up to 380, while torque comes in at a whopping 427 pound-feet. That gets the Cayenne Hybrid to 60 mph in 6.1 seconds, according to Porsche, just a half second slower than the V-8-powered Cayenne S.
Behind the wheel, the Cayenne Hybrid steps lively, a mashed accelerator delivering thrilling, and smooth, acceleration. Amid the mass of buttons on the center console, one labeled Sport makes the throttle more sensitive, putting power more quickly on tap.
But next to the Sport button sits one labeled E-Power, this button making the Cayenne Hybrid remain in EV mode as long as the electricity in its 288-volt nickel metal hydride battery pack holds out. The Cayenne Hybrid takes advantage of this electric power reserve to shut its engine down at stoplights, accelerate at low speeds using its electric motor, and do what Porsche calls "sailing" when coasting on the highway.
In that last mode, the engine shuts down at speeds up to 99 mph when you take your foot off the accelerator. A little bit of accelerator pedal in this mode, and the engine will stay off, the electric motor giving it the boost called for. But it is next to impossible to maintain freeway speeds on a level road in EV mode, and ascents will definitely require the gas engine to kick in. Drivers will have to get used to seeing the tach needle bounce up and down as the engine turns on and off.
With Sport mode off, the transmission reaches for its highest reasonable gear, keeping the engine humming below 2,000rpm to save gas. With eight gears to choose from, this transmission has an easy time finding its more efficient ratio.
In Sport mode and driving aggressively, fourth is often the power gear for the corners. Nicely molded paddles on the steering-wheel spokes control manual gear selection, but manual gear changes take place with the typical hesitation of a torque converter. If Porsche had really wanted to differentiate this car's performance from the Touareg Hybrid, it could have opted for a more sport-oriented transmission.
But Porsche put more effort into the Cayenne Hybrid's handling. The car may seem to be cruising through the turns, but a glance down at the accelerator shows it doubling recommended speeds with no strain. Inside-wheel braking, an electronic cornering technology that lightly brakes the inside wheel in a turn, helps the Cayenne Hybrid negotiate the curves.