This is the tale of a light right foot. Part of the fun of driving is being able to mash the throttle every now and then. But there is another way, where utmost control is exercised and impulses repressed to make a tankful of fuel go as far as possible. This is Audi's TDI Challenge. The goal: to drive a 2015 Audi A3 TDI from Albuquerque, New Mexico, to San Diego, California, on one tank of diesel.
The indirect route (not just a case of getting on Interstate 10 and slipstreaming a few trucks) is 834 miles, going through Sedona, Arizona. The tank holds 13.2 gallons. That works out to an average of 63.2 mpg. Fine in theory, but there are hills, traffic, and cities to deal with.
It is feasible, though, because Audi hired a hyper-miler expert to do a preliminary run. All it requires is to not use the air conditioning (even when driving through the desert), go slowly while a string of big rigs negotiate their way past, and no doubt employ a secret repertoire of special techniques to get maximum mileage from each squirt of diesel injected into those four cylinders.
This engine is the third and newest iteration of the VW Audi group's trusty, clean, and quiet 2.0L turbodiesel. It now makes 150 hp (10 more than before) but keeps torque at a still meaty 236 lb-ft, coming in strong at just 1,750 rpm. Where the previous version returned 30 mpg city, 42 mpg highway, and 34 mpg combined, this one is rated at 31/43/36. Our fuel-stretching specialist thinks those EPA numbers can be bettered just by sticking to the speed limits. But if this is a competition, there's no point in not being competitive.
One of the many great things about the new A3 is the trip computer, which is easy to navigate while still keeping hands on the steering wheel. It's useful to check the average consumption from time to time, but the instantaneous consumption readout really helps to focus the mind. On the first stretch from Albuquerque to Grants, there are plenty of uphill sections, and I'm torn between going slow and asking too much of the engine or putting my foot down, getting some momentum and staying in a higher gear. I go for momentum.
Some of the downhill stretches aren't sufficiently steep to throw the dual-clutch, six-speed transmission into neutral and coast while feeling smug about the 300-mpg figure that flashes up at those times. It still needs some throttle to keep the weight moving and have some kind of run-up to the next incline.
We stop at Grants to see the Ice Cave in El Malpais. It's a collapsed lava tube from a now-extinct volcano where the temperature never gets above 31 degrees F and the deepest ice is about 1,000 years old. From there, we trudge to Flagstaff and the other highlight of the day: the 89A that runs through the grandiose Oak Creek Canyon to Sedona. With the low sun hitting the lofty red rocks, it surely ranks as one of the great natural wonders of the world.
After day one, my driving partner (the excellent Nate Martinez of Motor Trend) and I have covered 372.7 miles at an average of 55.6 mpg. The trip computer gives our current range as 315 miles, with 461 more to go. There's no chance of cheating. Audi has placed a seal on the fuel cap, so if we stopped for an illicit couple of gallons, we'd be busted. But clearly, we need a better game plan.
We leave early next morning, with thousands of stars twinkling in a clear, pre-dawn sky. Arizona is so desolately majestic that I don't mind moving through it at an almost glacial pace. There are mountains, Alpine-like roads, and those cacti normally seen in cartoons—saguaro (Carnegia Gigantea)—are everywhere. Speaking of cartoons, it looks like we should be overtaken by the Road Runner (Velocitus Delectiblus) followed by Wile E. Coyote (Desertus-Operativus Imbecilius) on an Acme rocket sled. Everything else has been overtaking us on this trip, including a bus towing a porta-potty. Oh, the indignity. Luckily, vision is excellent for those many glances over the shoulder. Blind spot monitoring is an option, by the way.
On the west side of Sedona, one stretch of the 89A is a mountain road of smooth tarmac with some gorgeous bends. It's probably the one occasion ever in which I can turn to my driving partner and say I just took that last corner at 100 mpg. It's times like this that the A3's grippy front end comes into its own. The car turns in with precision and composure. Push it further and it'll understeer, then ease off the throttle and everything nudges back into shape. No all-wheel drive, just front-drive. But for something that's supposed to be the sensible choice, the A3 TDI is a surprising bundle of fun.
Rougher road surfaces bring more noticeable noise, though, and the suspension's sporty edge means a ride quality that sometimes gets close to jiggly. At no time did I actually need to sit in the back, but with the driver seat set up for me (an average-height adult male), I could get in the rear quarters easily, slide my feet under the seat in front, and not worry too much about hitting the headliner. The trunk also has more than enough space for the obligatory two sets of golf clubs.
We take the 89 from Prescott, through Yarnell. We go past real cowboys, working on ranches, riding horses, wearing hats and chaps (the cowboys, not us). Then we drop down to the long, straight 60 to eventually meet up with the 10 and stay on that while crossing into California. Then we take the 98, dip south on the 111, and head west again on the 8 that skirts close to the Mexican border and sends us over more switchbacks and through the Sahara Desert. It's not the Sahara, obviously, but the fine, pale yellow sands of Glamis Dunes are exactly how I'd imagine the world's largest desert to look. Whenever I fly across the United States, I always try to get a window seat and spend most of the journey looking at the amazing scenery below. Now I was right in it.
And the trip computer is telling us that we really will be right in it. In just a few miles. Every pulse (not even a prod) of the accelerator brings the real-time consumption figure down, along with feelings of stress and self-loathing. There's finally a point where we can rendezvous with some Audi techs and they can replenish the tank by a few gallons. It's immediately before a long uphill stretch that will surely pull the instantaneous mpg figure down into single digits.
After a total of 714.6 miles and an average of 59.7 mpg over two days, we decide to do the decent thing. The trip computer says we have 10 miles until empty. This is one of those situations where I wish I knew even yesterday what I know now, because the second day's average is 63.7, good enough to put the challenge within reach. The last 50 to 100 miles would still have been fraught, though, driving with the fuel gauge on E and with zero range in the display, trusting that Audi's engineers had been deliberately pessimistic and factored in a margin for error.
It's a sign of how good the car is (and especially how well-shaped and supportive the seats are) that I would have gladly done another 834 miles straight away. This premium compact sedan is ideal for someone who does a lot of driving and wants to be in a classy environment (a Bang & Olufsen audio system is on the options list) while keeping fuel bills manageable. And who wants it to be about more than just getting from one place to another. The TDI Challenge really has been the journey, not the destination.
Away from any unusual constraints, though, it's still possible to get mpg in the high 50s just by using common sense. Keep an eye out for traffic lights that have been green for a while; don't go speeding up to them only to brake hard when they go back to red and then sit there for a couple of minutes. Try to synch the approach for when they just turn green. Also, use the transmission in manual mode to stay in as high a gear as possible. In general, be gentle with driver inputs.
Should the desire to be less gentle arise, then the A3 TDI can hit 60 mph from standstill in 8.1 seconds before hitting a top speed of 130 mph. That's more than enough push for getting up to freeway speeds, powering out of bends, and for most overtaking situations.
Let's not forget that Audi has won Le Mans multiple times with diesel-powered race cars, so the company's knowledge of endurance, power, and reliability is pretty much unparalleled.
The trouble is that the great American motorist still finds it hard to accept diesel-powered cars. Gasoline is as much part of the culture as barbecued meat. In Europe, there are more new diesel cars sold than petrol drinkers. The old cliches of being slow, noisy, and dirty disappeared there years ago. And the irony is that diesel would suit the style of most American drivers. They love torque, which engines like this have by the bucketload. And with all those long, long, lonely roads that cross the heartland—exactly like those driven in the TDI Challenge—lower fuel consumption seems like a no-brainer.