By Chris Chase, CanadianDriver.com

The second generation of Audi’s flagship A8 sedan arrived in Canada in 2004, following its European introduction in late 2002. The lineup began as a single V8-powered model, the long-wheelbase A8L; a regular-wheelbase model and a second long-wheelbase variant powered by Audi’s W12 engine joined the range in 2005.

2006 Audi A8L

The A8 is notable for its aluminum construction and fully-pneumatic suspension, which can be raised and lowered by the driver, or set to lower automatically at highway speeds, for greater stability.

The base engine was a 4.2-litre V8 (335 hp/317 lb-ft of torque), while the W12 – essentially two Volkswagen VR6 engines “siamesed” at the crankshaft – displaced 6.0-litres and produced 450 horsepower and 428 lb-ft.

In 2006, the A8 got Audi’s single-frame grille, a controversial look that nonetheless gave the car more visual weight.

Find a used Audi A8 on AutoTrader.ca

For 2007, Audi added the S8, a high-performance variant powered by a 5.2-litre V10 shared by the smaller S6.

The styling was refreshed again in 2008, with a revised grilled (again) and LED taillights. In 2010, the S8 and long-wheelbase model W12 models were discontinued as Audi prepared for the arrival of the forthcoming 2011 model.

With the base V8 engine, the A8’s fuel consumption estimates of 13.1/8.8 L/100 km (city/highway) are more reasonable than you’d expect for a car this large. W12 and S8 models’ figures of 16.4/10.4 L/100 km and 15.9/10.3 L/100 km seem more in line with the kind of fuel consumption typically associated with luxury flagship sedans. A 2006 model I tested averaged 9.5 L/100 km on a highway trip from Ottawa to Hamilton, Ontario.

Typically, big German cars are expensive to maintain, and it appears the A8 is no exception. On 2004 models, at least, getting the oil changed is a pricey procedure thanks to the location of the oil filter. If you want to save a few bucks, take part of a Saturday and do it yourself; nothing about it is terribly difficult, but requires the removal of a couple of other components to get at the filter. This thread provides a good walk-through. (http://www.audiforums.com/forum/showthread.php?t=150293)

Most of the A8’s common issues are listed in this thread at AudiForums.com. Here’s a rundown of what you’ll find at that link. Note that while this thread says these problems are mostly limited to 2004 models, Consumer Reports lists the same troubles in 2005 and 2006 models (those are the only two years for which CR has data on the A8).

Overheating is common and typically caused by a bad thermostat. Radiator leaks are quite common, too; here’s another thread on that.

The front suspension’s upper control arm bushings are prone to wear, causing a clunking sound during turns. The cause, apparently, is that the A8’s larger control arms use the same bushings as the smaller A4, and the extra stress causes accelerated wear. CR also mentions the A8’s air suspension as something to watch for. These systems aren’t typically trouble-free in the long run and cost big bucks to repair.

2006 Audi A8L

Problems with a power trunklid that won’t open and/or close are caused by a bad motor or trunk hinges. If your A8 has a manual trunk, and you’d like to convert it to powered, this thread might help.

Early models have an engine coolant line that runs directly in the way of the space needed to remove the oil filter. The solution is to remove/replace the coolant line every time the oil needs to be changed, or simply bend it out of the way. The downside to the bend method is that if the coolant line begins to leak as a result, the engine might need to be removed to fix it.

The MMI (Multi Media Interface) system in the A8 is similar in purpose to BMW’s iDrive, consolidating many of the car’s systems into one control module. As with anything computer-driven, though, it’s prone to problems, some of which can be fixed with a software “reflash”. This thread at Audi-Forums.com discusses a number of problems with the MMI and navigation systems. If the hideaway MMI screen gets stuck behind the dash, the motor is shot and needs to be replaced.

Other items Consumer Reports recommends watching for are electrically-operated body hardware, like windows, mirrors and sunroof.

Neither the Insurance Institute for Highway Safety (IIHS) nor the National Highway Traffic Safety Administration (NHTSA) crash tested the A8. In fact, it doesn’t look like anyone has; not even EuroNCAP has crash safety data on this big Audi.

According to Canadian Black Book, used A8 values range from a low of $23,050 for a 2004 A8L to a high of $121,100 for a 2009 A8L W12. Suggested prices for the S8 start at $83,025 for a 2007 model to $99,625 for a 2009. To be very honest, the A8’s base engine is plenty for this car, and presents an excellent balance between performance and economy, and avoids the W12’s extra layer of complication when it comes to make repairs.

It’s difficult to find any example of this car unattractive, but I’m partial to the slightly sharper, tauter lines of the 2008 redesign. The short-wheelbase V8 version is worth $56,225, while the long-wheelbase car is valued at $60,275, both of which represent about 60 per cent of the original MSRP. It’s hard to say no to numbers like that, considering it isn’t hard to option a new A4 up to $60,000, but while a 2008 might have a bit of its four-year/80,000 km warranty left, you’re best to save up for when it expires so you can afford to pay for whatever might go wrong.

Shop for an A8 with detailed maintenance records and go through these before you buy, looking for evidence of whether the trouble spots mentioned above have been an issue with this car. Have the car looked at by a trustworthy mechanic, too, preferably one who has experience with the A8, or at least with high-line luxury cars in general and ask him or her to pay special attention to the air suspension; while test driving the car, press every button in the car and explore the MMI system to make sure all of the car’s advanced features work. After all, the goodies are a big part of what make this type of car special.

Pricing

Black Book Pricing (avg. retail) August 2010:

Online resources

I had good luck digging up useful info at both AudiForums.com and AudiWorld.com. AudiForum.us is a decent spot, too. AudiForum.ca is Canadian, but lumps all generations of the A8 together in a section that’s not all that busy; same goes for Audi-Forums.com.

Recalls

Transport Canada Recall Number: 2005538; Units affected: 73

2006: On certain vehicles, an improperly routed ground in the front passenger-side airbag and seat heater harness may cause signal interference. This can result in the deactivation of the passenger-side frontal airbag under circumstances when it should remain activated. If this condition occurs, the passenger-side frontal airbag would not deploy in the case of a frontal crash, possibly exposing the occupant to risk of injury. Correction: Dealers will modify the wiring harness.

Transport Canada Recall Number: 2006203; Units affected: 365

2004-2005: On certain vehicles the drivers frontal airbag may not inflate as designed, which could cause driver injuries in a crash. Correction: Dealers will replace the driver airbag.

Transport Canada Recall Number: 2006316; Units affected: 252

2006-2007: On certain vehicles, in cases where a weak battery exists, it is possible that a low voltage condition could cause the airbag control unit to improperly set a fault code. If this occurs, the passenger-side frontal airbag will become deactivated and would not deploy during a frontal crash. As a result, a passenger-seat occupant could receive more severe injuries. Correction: Dealers will update the airbag control module software.

Crash test results

National Highway Traffic Safety Administration (NHTSA)

Insurance Institute for Highway Safety (IIHS)

Used vehicle prices vary depending on factors such as general condition, odometer reading, usage history and options fitted. Always have a used vehicle checked by an experienced auto technician before you buy.

For information on recalls, see Transport Canada’s web-site, www.tc.gc.ca, or the U.S. National Highway Transportation Administration (NHTSA)web-site, www.nhtsa.dot.gov.

For information on vehicle service bulletins issued by the manufacturer, visit www.nhtsa.dot.gov.

For information on consumer complaints about specific models, see www.lemonaidcars.com.

Chris Chase is an Ottawa-based automotive journalist. He is a member of the Automobile Journalists Association of Canada (AJAC).

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