The 2008 Detroit Auto Show will be remembered as the year many auto makers plugged in, while a few came unplugged.

Withdrawing from the show were Porsche AG and Aston Martin Lagonda Ltd.

Porsche officials say the decision was market driven, and that the brand does not sell many vehicles in Detroit. Aston Martin was no longer part of the Ford Motor Co. pavilion, as Ford sold its majority stake in the British luxury brand to a consortium led by Prodrive Ltd.

The departure of the niche players from the show was overshadowed by talk of fuel economy, weeks after President Bush signed stiff new corporate average fuel economy legislation requiring new vehicles to achieve 35 mpg (6.7 L/100 km) by 2020.

Plug-in hybrid-electric vehicles were on display at the Ford, General Motors Corp. and Toyota Motor Corp. pavilions and at smaller booths occupied by Fisker Automotive Inc., China's BYD Auto Co. Ltd. and AFS Trinity Power Corp., a privately held company based in Bellevue, WA.

Even the exotic cars that tend to serve as eye candy on the show floor were recast for environmentally leaning buyers.

Ferrari SpA - whose customers generally can afford gas guzzler taxes - unveiled a concept F430 Spider Biofuel designed to run on E85 ethanol and displayed a pristine V-8 with green-painted spark plug coil packs, fuel injectors and fuel rails.

Well-heeled environmentalists will have to wait: For now, the F430 Spider Biofuel is purely a concept, and there are no immediate plans for production.

At the Audi AG stand, the dangerously sexy R8 super car rolls out with a new 5.9L V-12 turbodiesel, derived from the 5.5L 650-hp diesel that powered the R10 racecar to wins at the 24-Hours of Le Mans in 2006 and 2007.

However, the concept V-12 must make do with a mere 500 hp. The engine's twin turbochargers add up to 38 psi (2.6 bar) of boost pressure and help deliver a whopping 738 lb.-ft. (1,000 Nm) of torque.

For its green credentials, the R8 V-12 TDI employs AdBlue urea-injection technology to break down oxides of nitrogen emissions before they leave the tailpipe. Audi says the concept engine meets Euro 6 emissions standards likely to take effect in 2014.

Another sleek model that blended performance with fuel-sipping technologies was Mitsubishi Motors Corp.'s Concept-RA coupe, with a turbocharged 201-hp 2.2L DOHC diesel, common-rail direct injection, continuously variable valve timing and dual-clutch gearbox.

The vehicle is constructed of low-weight, earth-friendly materials, such as an aluminum spaceframe and recyclable plastic resin for the hood, fenders and outer panels. To meet U.S. Tier 2 Bin 5 emissions standards, the Concept-RA employs catalyst technologies such as a diesel-oxidation catalyst, nitrogen-oxide trap catalyst and diesel-particulate filter.

Mitsubishi did not say whether the concept is the basis for a production model or possibly a glimpse at the next Eclipse.

At the GM pavilion, the Saab 9-4X BioPower Concept optimizes ethanol use and confirms the Swedish division's much-anticipated entry into the cross/utility segment.

Saab hasn't said when the all-wheel-drive 9-4X goes on sale in the U.S. Power comes from an all-aluminum, 2.0L 4-cyl. engine optimized for E85 ethanol. The turbocharged mill delivers 300 hp and 295 lb.-ft (400 Nm) of torque, but trims greenhouse gas emissions vs. a comparable conventional engine.

Saab already sells BioPower-branded versions of its 9-3 and 9-5 sedans in Europe and Australia.

GM made a splash at the 2007 Detroit auto show with its Volt plug-in hybrid, and this year's event brought the Cadillac Provoq, a hydrogen fuel-cell CUV concept that advances the auto maker's E-Flex propulsion system.

The 4-door, 5-passenger Provoq - hinting broadly at Cadillac's BRX in about two years - uses a fuel-cell stack to power three electric motors - a 92-hp (70-kW) co-axial drive system for the front wheels and individual 54-hp (40-kW) wheel hub motors to move the rear wheels.

GM predicts 0-60 mph (100 km/h) acceleration of 8.5 seconds and a top speed of 100 mph (160 km/h). The electric motors provide instantaneous torque. Two 10,000-psi (700 bar) composite storage tanks located beneath the rear cargo floor hold 13.2 lbs. (6 kg) of gaseous hydrogen to feed the fuel stack.

A lithium-ion battery pack stores up to 9 kWh of electric power with peak power of 60 kW. The concept will travel 300 miles (483 km/h) on one fill-up. GM says the Provoq achieves 280 of those miles (450 km) from hydrogen and the remaining 20 miles (32 km) via battery power.

GM also showed its Shanghai-built Buick Riviera hybrid concept coupe, underscoring the brand's presence in China, where GM sold 1.03 million vehicles last year.

First unveiled at China's Auto Shanghai 2007, the gull-wing, front-wheel-drive Riviera was penned by the Pan Asia Technical Automotive Center, a Shanghai-based design and engineering joint venture between GM and partner Shanghai Automotive Industry Corp. (SAIC).

Compact CUVs were plenty popular this year at the Detroit show.

Mercedes-Benz debuted its GLK, which will be the fifth, and smallest, CUV in the tri-star lineup when it goes on sale in Europe and the U.S. next January.

Daimler AG Chairman Dieter Zetsche says the new CUV will get 35 mpg (6.7 L 100/km) thanks to the all-new 2.2L 4-cyl. diesel that incorporates the latest piezo-injector technology, 2-phase turbocharging and 29,000 psi (2,000 bar) injection pressures to deliver 204 hp and 369 lb.-ft. (500 Nm) of torque.

The new diesel also features AdBlue urea injection and a SCR catalyst that enables the mill to meet the toughest emissions standards.

The system will be added to Mercedes' diesel-powered R- M- and GL-Class vehicles in the year's second half, meaning even the auto maker's largest diesel-powered vehicles can be sold in all 50 states.

Toyota Motor Corp. previewed its 5-passenger '09 Venza CUV, which goes into production in November in Georgetown, KY, for sale later this year and designed and engineered almost entirely in North America.

The Venza arrives with a choice of two powertrains: a 2.7L 4-cyl. engine mated to a 6-speed automatic transmission and a 3.5L 6-cyl. mill with a 6-speed gearbox.

Toyota executives confirm the slow-selling Camry Solara will exit production once the '08 model year ends, as the Venza takes its spot on Georgetown's No.2 production line.

For a short time, as Solara production winds down and Venza output ramps up, there will be four models built on the line, including the Camry and Camry Hybrid sedans.

Toyota expects to sell 75,000 Venzas annually.

Ford's Lincoln luxury division rolled out its MKT CUV concept, which shares a platform with the forthcoming '09 Ford Flex.

Unlike the 7-passenger Flex, the dramatic MKT provides seating for four, with a cavernous bustle-back cargo hold behind the second-row seats. The oversized seats are meant to emulate those found in first-class aircraft cabins. Ford says the concept's interior boasts eco-friendly materials.

The nifty center stack features a new solid-state lighting technology that allows projections - previously relegated to flat surfaces - onto contoured surfaces in 3-D. Instrumentation also is decidedly high tech, with light-emitting diodes positioned so light appears to emanate from the center of three circular dials.

The MKT's E85-capable 3.5L V-6 produces 415 hp and 400 lb.-ft. (542 Nm) of torque and is mated to a 6-speed transmission.

Also in the CUV sector, Fuji Heavy Industries Ltd.'s Subaru of America Inc. introduced an all-new, third-generation '09 Forester.

Subaru says the new model is bigger and safer than the one it replaces, with more rear-seat legroom. The vehicle comes with a standard 2.5L 170-hp engine, or an optional turbo version producing 224 hp.

The '09 model will be in showrooms by early April. The Forester's U.S. sales totaled 44,600 in 2007.

GM managed to deliver a surprise at the show with its Cadillac CTS concept coupe.

The long-rumored coupe caught the motoring press off guard, as it was the one introduction GM did not brief journalists about ahead of the show.

Although the CTS coupe matches the length of its production sedan sibling, it sits 4 ins. (10 cm) lower, with wheels pushed to the corners for a sleek, “crouching-cat” look.

The coupe receives oversized, 20-in. chrome, 7-spoke wheels up front and a 21-in. set in the rear.

Hyundai Motor America steps into the U.S. luxury segment by unveiling its new Genesis sedan, now on sale in South Korea. The rear-drive '09 Genesis will be available with three engines - including Hyundai's first V-8 - when it goes on sale in the U.S. this summer.

Hyundai estimates the all-aluminum, Tau 4.6L engine will produce 368 hp and 324 lb.-ft. (439 Nm) of torque in the Genesis.

Hyundai also plans to retail a coupe version of the Genesis in the near future. A concept was shown at last fall's Los Angeles auto show.

And although the Hyundai Tiburon will exit the U.S. market at the end of the year, coupe fans will get two new models in its place, a Hyundai official tells Ward's at the show.

In addition to a coupe version of the rear-drive Genesis, Hyundai will offer an entry-level coupe based on the Veloster concept unveiled at last spring's Seoul auto show. The two vehicles will bracket the segment where the Tiburon lives.

Volkswagen AG unveiled the Passat CC 4-door coupe, as VW intends to kick off a new sales and brand-polishing drive in America to hit 800,000 sales annually by 2018.

The Passat CC's high belt line and dramatic styling are an attempt to recast VW's U.S. image and lift it upward, says Stefan Jacoby, head of VW in the U.S.

The car goes on sale later this year, and Jacoby says volumes will total about 20,000-25,000 units in the car's first full year.

Also expected to help boost VW volume is a new minivan, a derivative of the Chrysler Town & Country that Chrysler LLC will supply beginning later this year.

Elsewhere in the VW family, Audi packs more punch into its diminutive TT sports car, with a new 272-hp TTS rendition unveiled at the show.

The TTS, which will hit European dealer showrooms in early summer and U.S. outlets in November (as an '09 model), features a modified version of the TT's direct-injected, turbocharged TFSI 2.0L gasoline engine that boasts 258 lb.-ft. (350 Nm) of torque in a wide bandwidth of 2,500-5,000 rpm.

Currently, the TT's most powerful engine is the 250-hp 3.2L DOHC V-6 that delivers 236 lb.-ft. (320 Nm) of torque. The standard 2.0L is rated at 200 hp and 207 lb.-ft. (281 Nm) of torque.

On the CUV front, Honda unwrapped its upcoming '09 Pilot prototype, boasting a more utilitarian look, improved interior space and its retained unibody chassis.

The next-generation Pilot, which first debuted as a '03 model in July 2002, goes on sale in the U.S. this spring.

Unlike many current CUVs, Honda says the new Pilot's third-row seats are extremely roomy and can accommodate an “above-average-size adult male.” Honda last year transferred production of the Pilot exclusively to its Lincoln, AL, plant from Alliston, ON, Canada.

Kia Motors America Inc. unveiled its new Borrego, which will be the largest vehicle Kia has ever sold in the U.S. with a wheelbase of 114 ins. (290 cm) and length of 192 ins. (488 cm).

The Borrego will be mated to Kia's most powerful engine ever, the new Tau 4.6L V-8, which it will share with sister marque Hyundai. The engine will make 300-hp plus in the Borrego. A smaller, 3.8L V-6 engine also will be available.

Land Rover described its LRX concept as a “cross coupe,” designed to appeal to a younger, more female demographic - areas where the brand has shown weakness in the past.

Equipped with all-wheel drive, the LRX offers a nod to green technology, with a 2.0L turbodiesel capable of running on biofuel.

For complete coverage of NAIAS, go to WardsAuto.com and click on “Special Reports and Show Coverage” at the bottom of the page.