As we raced the 2010 Acura RDX along winding mountain roads, feeling out corners carefully so as not to send this small SUV tumbling, we wished the turbocharged engine and all-wheel-drive system were in a completely different car. Throw this running gear into a small coupe, ditch the five speed automatic for a slick six-speed manual, and Acura would have an impressive replacement for the discontinued RSX.
But as it is, the 2010 RDX competes in an extremely crowded market, against the likes of the, the , and the . Somewhere in Acura headquarters, someone looked at all these other small SUVs, and decided to jump on the bandwagon, going for mass-market popularity as opposed to a niche sports car. But the power train engineers seemed to be building a different car, and were probably surprised to see their engine sitting between the high front wheels of an SUV.
That engine and the all-wheel-drive system, and to some extent the automatic transmission, make the 2010 RDX one of the sportiest drivers amongst small SUVs, but the turbocharged engine doesn't do well with the car's near-2-ton curb weight. A V-6 would have given it smoother acceleration and probably delivered better fuel economy.
The power train is comprised of a 2.3-liter four-cylinder engine with Honda/Acura's i-VTEC technology, controlling valve timing and lift, a variable flow turbocharger with a peak pressure of 13.5 psi, and a five-speed automatic that includes sport and manual shift modes. The turbocharged engine puts out 240 horsepower at 6,000rpm and 260 pound-feet of torque at 4,500rpm.
Acura's only turbocharged engine might have been better suited to a light sports car.
Although Acura claims its variable-flow turbocharger minimizes lag, we beg to differ. The gas engine gives the RDX adequate push from a stop, and then the turbo kicks in when the engine hits about 2,500rpm. At that moment, a very perceptible power boost hits the RDX, giving it uneven acceleration. During passing maneuvers, attempting acceleration at speed, the turbo's late kick made it difficult to judge safe distances. The turbo lag is not as extreme as with the, but it is definitely there.
In general, a turbo is a good way to increase power without negatively affecting fuel economy as much as more displacement would. But that equation doesn't work out so well in the RDX. EPA fuel economy is 17 mpg city and 22 mpg highway, pretty dismal numbers for a four-cylinder engine. In our mixed freeway, mountain highway, and city driving, we achieved an average of just 18.3 mpg. The bigger, with its 3.5-liter V-6, got better fuel economy.
The five-speed automatic shifts readily in manual mode.
Of course, that Lexus also has a six-speed transmission, versus the five-speed automatic in the RDX, which will affect fuel economy. We would have preferred an extra gear in the RDX transmission, but we were impressed with its capabilities. In manual mode, it changed gears quickly every time we pulled one of the paddle shifters on the steering wheel, without a lot of the torque converter slushiness that usually comes with automatics. Its sport mode kept the engine speed high, but didn't downshift aggressively as we braked before a corner.
Our RDX came with Acura's Super Handling All Wheel Drive system (SH-AWD); a front wheel drive RDX is also available. This system holds the road incredibly well. As we dashed over wet roads on a drizzly day, we could feel the system work to keep the RDX on the pavement, especially in the corners as we put more and more speed on. Working against it was the car's high center of gravity, hence our wish for a low-slung sports coupe that could really take advantage of this technology. SH-AWD not only transfers torque dynamically from front to rear; it also sends it between the two rear wheels as needed. A neat little torque graphic on the instrument cluster shows second-by-second torque distribution, but you can't really monitor it when performing maneuvers that make it change.
The cabin of the 2010 RDX doesn't feel particularly luxurious, although it looks nicer than a typical economy car. There are hard plastics, but Acura finishes them well. The buttonitis affecting many Acura models is kept in check on the stack, but still overwhelms the steering wheel.
This big controller looks awkward, and the onscreen interface isn't all that intuitive.
Acura uses a big joystick/knob, set below the car's LCD, for controlling audio, navigation, and phone functions. It is not the most elegant-looking controller, and it uses a similar paradigm as BMW's iDrive and Mercedes-Benz's COMAND system for alphanumeric inputs. You twist the knob until a letter or number is highlighted on the LCD, then press it to select. Entering long names gets tedious quickly, but Acura speeds the process with predictive text. The main problem with this interface is that it's not always clear when you need to push the joystick up or down, or to either side.
The navigation system isn't up with Acura's latest, the hard drive-based system we saw in the. The RDX still relies on a DVD-based system. Map modes are restricted to 2D, but it does feature integrated traffic and weather, delivered through XM satellite radio. The traffic feature alerts you to slow traffic and different kinds of incidents, such as road construction and collisions. Program a destination, and the system dynamically routes around traffic problems.
Route guidance is fairly basic, but practical. The system doesn't do text-to-speech, but its guidance graphics are clear. Acura has included Zagat ratings in its points-of-interest database for a few years now, helping you determine a restaurant's quality instead of blindly choosing by cuisine. Not only are the ratings included, but you can also access the written reviews--a big plus.
Zagat ratings in the navigation system's POI database are very detailed.
As the navigation system is still DVD-based, there is no onboard storage for music, as there is in the TL SH-AWD. But for the 2010 model year, the RDX does gain iPod integration and Bluetooth audio streaming to add to its other audio sources--an auxiliary input, satellite radio, and an MP3- and DVD-audio-compatible six-disc in-dash changer. The interface for iPod integration allows music selection by artist, album, and genre, as we would expect. These audio sources play through 5.1 channel audio, the ELS branded premium system. It uses 10 speakers and produces excellent sound quality. Trying out different tracks with this system, we were impressed by its staging--the capability to precisely place specific instruments around the cabin. With the equalizer settings flat, the audio seems tuned more for good high-frequency reproduction, but tweaking the bass and subwoofer gives music some depth.
The Bluetooth phone system seems to have gotten an update from the previous RDX model year. It now copies over a paired phone's contact list, making it possible to select people by name on the car's LCD. The voice command system says that it will also dial by name, but we could not get that feature to work.
This double bank of buttons controls two separate voice control systems.
In general, the voice command system in the RDX is very good, letting you control a wide number of car functions by voice. Navigation, audio, and climate control are all easy to use by voice, and the car even responds to questions such as "What time is it?" Voice command also works for making calls, to some degree, but this is actually a separate voice command system, with its own set of buttons on the steering wheel. We've pointed out the problem with this double set of voice command buttons on previous Acuras; it hasn't yet been corrected in the RDX.
Although we like the idea of the turbocharged four-cylinder engine in the 2010 Acura RDX, in practice it isn't all that effective. Mileage is poor and acceleration is uneven. But the RDX earns points for its all-wheel-drive system and solid-feeling automatic transmission. The cabin tech earns points for the excellent sounding audio system, and it gets a boost from traffic, weather, and Zagat ratings on the navigation system. But in too many other ways this cabin gear falls behind competitors. The interface design for the cabin tech is about average, suffering from some usability issues. As for the exterior, from many angles the RDX looks like any other small SUV, but Acura does put a distinct grille on it.
|EPA fuel economy|
|Observed fuel economy|
|Bluetooth phone support|
|MP3 player support|
|Other digital audio|
|Price as tested|