In spite of some recent hiccups with plans by other manufacturers to introduce new diesel models in the U.S. market (see here), Audi is one company that at least publicly remains fully committed to oil burners. During the recently completed Audi Mileage Marathon, the company brought over examples of most of its lineup powered by diesel engines including the TT TDI. One of the few diesel models that was not included was the A5 TDI. The A5 debuted in 2007 as a coupe built on the company's new B8 platform which also forms the basis of the 2009 A4 sedan.
The A5 TDI is unfortunately not yet available in the U.S. market so we got our example courtesy of Honeywell. Honeywell's Garret division is one of the largest manufacturers of turbochargers which of course are a critical part of any modern diesel engine. Earlier this year we also tested a BMW X5 diesel and an Audi Q7 4.2 TDI from Honeywell's fleet. Like the A4s, Q5s and Q7s that participated in the marathon, this A5 came to us powered by a 3.0L V6 diesel. Read on after the jump to find out how voluptuous body work, high performance and fuel economy get along.
Photos Copyright ©2008 Sam Abuelsamid / Weblogs, Inc.
The A5 shares its mechanical architecture with the A4 which comes in four door sedan and wagon body styles. Unlike all the so-called four-door coupes like the new Volkswagen CC, and Mercedes CLS, this A5 is a true two-door coupe. It's also more than just a two-door version of the sedan. While it carries the same design language as other contemporary Audis, it's both lower and wider than the sedan. The coupe spans about 2.6 fewer inches from bumper to bumper and 2 inches between the axles. It also stands about 2 inches lower than the sedan.
From the front, the A5 is immediately recognizable as an Audi including its massive grille and composite headlamp clusters. Like its siblings, the clusters have a row of LEDs for the daytime running lights that Audi designers have dubbed eye-liners. The xenon lights have automatic leveling adjustment to make sure they are aimed correctly regardless of the vehicle loading. When the lights come on they definitely get people's attention. Moving down the sides of the body, the belt-line crease has more of a curve as it sweeps over the fenders then the sedan. The body work below the crease sticks out further on the coupe while on the sedan this is reversed with a slight overhang of the upper body.
The coupe and sedan both have a similar up-sweep to the rocker panel crease that comes together with the sloping rear glass, short rear deck and slight downward slope at the rear end of the belt-line crease to produce a nice tight rear end. The trunk lid opens wide onto a reasonably-sized 16.1 cu. ft trunk, a space that can be expanded by folding down the rear seat back in a 60/40 split.
Under the hood resides Audi's 3.0L V6 TDI putting out 240 hp and 369 lb-ft of torque. In Europe, buyers can still choose between this newer engine with it's common rail injection system or the older 2.7 TDI now also equipped with the common rail system rather than the older pump-nozzle injector system with a pump-nozzle injector system. The so-called "pumpe-duse" is the same technology that was used on the former 1.9L four cylinder in VWs and Audis and the 5.0L V10 TDI that was available in the Touareg until this year. The pumpe-duse system had a high pressure pump integrated with each individual injector. The common rail system uses a single high pressure fuel rail with a high pressure pump to feed all the injectors on each bank of cylinders.
The common rail system has more precise control of fuel flow, allowing for lower consumption and emissions, with more power. The ability of common rail systems to execute up to seven separate injection pulses per ignition cycle also helps spread out the combustion, lowering the temperature and NOx production as well as almost eliminating the clatter traditionally associated with diesel engines.
The A5 we had actually didn't seem to be running quite right, as it had a fairly strong shake for the first minute or so after a cold start. This is a phenomenon that I haven't noticed with any of the vehicles I've ever driven with this engine. This problem may well be a relic of an accident this particular car was involved in the hands of another writer last winter, the week before we were scheduled to get into it originally. Once the engine warmed, the shake disappeared completely. Underway, like other modern diesels the noise and vibration characteristics of this engine were as good as any modern gas engine.
The A5 sent its immense torque to the road through Audi's usual Quattro all wheel drive system and a six speed manual gearbox. The latest version of the Quattro system retains a Torsen center differential that can automatically send more torque to the front or rear axle depending on which end has more grip. Unlike earlier Quattro generations that always had an even 50/50 nominal front/rear split, the new generation as used on the A4/A5 splits torque 40 percent to the front and 60 percent to the rear. Since the front wheels are doing the steering, this helps give a more even balance and reduces understeer.
Controlling all of this hardware is a pleasure for the driver of the A5. The interior will be immediately familiar to any driver of a recent Audi and that's generally a good thing. The thick rimmed three spoke steering wheel is adjustable for reach and height and features controls for the audio system on the 9 and 3 spokes. The gauges are large and clearly legible. A pair of multi-function control knobs on the center stack combine with a reasonable number of buttons and the large central display screen manage the audio system, climate controls and heated seats. The seats in this A5 were the optional sport seats with more aggressive side bolsters, inflatable lumbar support and adjustable thigh support allowing those with longer legs to get more comfortable.
The coupe body style means that although the dash and controls look the same as the sedan, you sit noticeably lower than in the A4 and the 3 inch shorter wheelbase is readily apparent in the back seat. Leg and headroom are both diminished although the back seat is still usable by kids and adults for short hops. The six-speed gearbox has a smooth precise shift action although the throws feel a bit on the long side. This particular example was not equipped with Audi's new Drive Select system which includes adjustable dampers, steering and throttle control.
An electric power steering system is standard across the board on A4s and A5s. However, without Drive Select, below about 15 mph, the steering effort feels way too light. Once you get above that speed, things tighten up nicely and the steering feels great. The suspension is nicely damped and provides an excellent balance between ride and handling capability. The body stays flat around corners and the seats hold you in place in spite of lateral cornering forces. The engine provides wonderful mechanical sound free of clatter that urges you to drive and feels like an expensive high performance engine.
As a premium brand, Audi is making a point of emphasizing that its diesel engines still provide all the performance a driver would expect of a German sports coupe or sedan (or SUV for that matter) with much improved fuel efficiency. It's all about guilt-free pleasure. The A5 certainly meets those criteria. The A5 TDI is rated at 35.6 mpg (U.S.) combined on the EU test cycle and averaged 32.5 mpg during our time with the car. For a mid-sized coupe that's pretty impressive in real world driving. From a standing start, Audi claims acceleration to 62 mph in 5.9 seconds for the manual transmission model like ours, a number that's consistent with what we felt. This 3,500 lb coupe accelerates like a rocket, especially when its already moving.
There's no doubt that cars like the A5 TDI are not meant to compete with the likes of the Prius or Civic hybrid. With a price that would like be around $45,000 (the 2009 A5 3.2 FSI starts at $$40,700) if it were offered in the U.S. market, the A5 doesn't come cheap. But with the looks and performance it offers, combined with excellent fuel economy, anyone looking for something in this segment would have to give it serious consideration.
Photos Copyright ©2008 Sam Abuelsamid / Weblogs, Inc.