2011 Hyundai Tucson : Driving Impressions

Driving Impressions
The Hyundai Tucson is reasonably agile and responsive, competitive with the other small utilities in its class, such as the CR-V and Escape.

Hyundai's 2.4-liter engine is smooth and quiet in normal driving, but accelerating hard onto a freeway to join the flow of traffic, its thrust is only adequate and the yowl it makes reminds you that it has a small, four-cylinder engine. The 2.4-liter engine is rated 176 horsepower at 6000 rpm and 168 pound-feet of torque at 4000 rpm. It's comparable to the other four-cylinder engines in this class, which do not offer the thrust of a more powerful but more expensive V6. Fuel economy for the 2.4-liter Tucson engine is 22/31 mpg with front-wheel drive.

The Hyundai-designed 6-speed automatic transmission is smooth-shifting and excellent, giving the Tucson a big advantage in efficiency over other vehicles in its class. Additionally, its manual shifting capability is particularly good. In all but the most dramatically ill-advised shift requests, it gives you the gear you command.

The Tucson GL 2.0-liter engine features dual overhead camshafts, four valves per cylinder, continuously variable valve timing and a variable intake system. The 2.0-liter produces 165 horsepower at 6200 rpm and 146 pound-feet at 4600. We haven't driven the Tucson GL with the 2.0-liter engine. As the GL is not significantly lighter than the GLS, we have to suspect that performance suffers accordingly. The automatic 2.0-liter is the fuel-economy champion of the line, albeit only by a whisker, with an EPA rating of 23/31 mpg City/Highway. EPA mileage estimates for the 2.0-liter with manual transmission are only 20/27 mpg.

In states that follow California regulations, the GLS and Limited are Partial Zero Emissions Vehicles (PZEV), with horsepower reduced to 170 hp and torque to 163 pound-feet. Pricing and equipment remain the same, so you can satisfy your environmental good intentions with little or no sacrifice.

The motor-driven electric power steering is one of the Tucson's greatest strengths. We found it perfectly calibrated, giving firm steering response and flawless road, leaving us no excuse to become uninterested in the driving experience. Absolutely first class. For 2011, Hyundai says it's even better integrated into the vehicle's Electronic Stability Control.

Ride and handling are good. In corners, the chassis had only mild roll, as would be expected of a vehicle engineered and tuned in Germany.

However, we noted a significant difference between the front-wheel-drive and all-wheel-drive versions. Ride quality with the all-wheel-drive models was noticeably harsher than that of the front-drive versions. This proved particularly true when driving the top-of-the-line Limited AWD with 18-inch wheels and therefore tires with shorter sidewalls. This is not to say that the AWD chassis is terrible, and if your planned use for your vehicle dictates all-wheel drive for climatic reasons, then the AWD Tucson will serve your purpose admirably. But if you have no particular need of all-wheel drive, save some money, and get a gentler front-wheel-drive package.

We found the brakes felt good with firm pedal feel and exemplary modulation, meaning nice, smooth, precise stops. All in all as utilities go, a satisfying driving package.

*newcartestdrive.com

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2011 Hyundai Tucson : Walkaround and Interior

Walkaround

This crossover SUV is nothing if not modern. The Hyundai Tucson takes advantage of the current European taste for dynamic thrusting forms and aggressive angularities. It has swoopy lines darting to and fro along its flanks, nose and tail. The side windows have not the slightest hint of being rectangular, with the little triangular windows behind the C-pillar almost squinted shut.

The Tucson has an athletic, muscular look, the four wheels barely contained by their swollen, stuffed-tight wheel arches. A huge, deeply slanted windshield provides excellent forward perspective for the driver, but for rear seat passengers, looking out of the Tucson's narrow side windows is a little like peering out the gun slit of an armored car.

And there will be those who find the Tucson's exterior a little busy looking, while others will find that standing next to the Tucson and looking down its door sides, it looks oddly slab-sided, bigger and heavier than it really is.

As always, there is ample room for debate about the Tucson's styling. The one point that is not debatable is this crossover's high expectations. Its styling is up to the minute, as aggressive as any crossover in the world market. For those youngish families with a taste of sportiness, Hyundai has opened the door wide.

Interior Features

The Hyundai Tucson is roomy and comfortable. The front seats are excellent both in terms of firm support and quality leather. The one-touch up/down driver's power window is one of those conveniences that once you've gotten used to it, you'll never be satisfied with less. Back seat room is lavish for two, adequate for three. If you're looking for a third row, forget it. This is a compact crossover.

The first thing that strikes you climbing into the Tucson is its reassuring feeling of harmony and simplicity. This car's chief designers and stylists may have been German, but in the Tucson there is no hint of the German tendency towards self-indulgent complexity, of making you learn all over again how to do something you already know perfectly well how to do. Decidedly to the contrary, the Tucson offers excellent ergonomics, that all but lost discipline of making a car's controls self-explanatory and intuitive. This Hyundai gets an A-plus in the avoiding annoyances category.

The dashboard's black pebble-grain covering is handsome and anything but econo class. The dashboard instruments are straightforward and dignified, with a water temperature and fuel gauge delivered in electronic readouts. To the left of the steering column are controls for hill assist, a stability-control off switch and the differential locker control. Cruise control and audio switches are provided on the steering wheel, with phone controls partially hidden inside the wheel rim.

The center console is simply laid out, offering audio controls, a navigation system and Bluetooth MP3 capability. Here we encountered one weakness in the Tucson, its forward-slanting navigation screen was all but blinded by glare on sunny days. On the other hand, it is blessedly straightforward to use, with a proper radial knob provided for tuning the audio. Defrost front and rear and individual seat-heater controls are easily selected, while XM is the satellite server of choice, and it should be. Life should always be this easy. But in too many other cars, it isn't. The Tucson interior deserves an A.


*newcartestdrive.com

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Jaguar Debuts C-X16 Concept Hybrid Sports Car

The Frankfurt Auto Show opened Monday with Jaguar making an impressive pseudo-green splash, debuting a 375-horsepower supercharged 3.0-liter V6 linked to a high-performance electric motor that boosts output by up to 94 hp in short bursts. Inspired by last year's C-X75 concept, the C-X16 two-seater concept integrates an electric motor with the transmission, along with a Kinetic Energy Recovery System (KERS) adapted from Formula 1 that  replenishes the lithium-ion battery pack through brake regeneration. The hybrid add-on provides short bursts of additional power -- up to 94 hp and 173 pound-feet of torque -- at the touch of a button on the steering wheel.

The electric motor with KERS saves fuel compared to using a V8 to achieve similar horsepower, but Jaguar spokesmen weren't willing to discuss the model's fuel economy. They were, however, delighted to report that the car accelerates from zero to 60 in less than 4.4 seconds and has a top speed of 186 mph. The front-mounted V6 is a new direct-injection prototype unit based on Jaguar's familiar AJ-V8 and develops 332 pound-feet of torque, driving the rear wheels through a ZF eight-speed automatic gearbox.

The swoopy Ian Callum-designed aluminum-bodied coupe is finished in gunmetal, its lines reflecting what Jaguar described as the next evolution in the brand's design language. The C-X16 boasts a signature trapezoidal grille, similar to the one on the C-X75, as well as such defining elements as a clamshell hood, carbon-fiber front splitter and side sills, plus flush door handles that pop up when touched. The car rides on 21-inch wheels and tires and has unusually strong aluminum architecture and, reportedly, a perfect 50:50 weight distribution. The "1+1" cockpit of the C-X16 is equally eye-catching, finished in Vermillion Red and trimmed in leather, Alcantara, anodized aluminum, piano black, dark chrome and carbon fiber.

"The C-X16 is our compelling vision for a 21st-century Jaguar sports car," said Adrian Hallmark, Jaguar's global brand director. "It embodies the established Jaguar strengths of sensual design, animal-like agility and inspirational performance and combines these with attributes that set us on a course to create sustainable sports cars of the future."

*autoobserver.com

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History of all wheel drive explained

Why is it important to know how your all wheel drive works? First, it may appear that your all wheel drive system is not meant to be used on-road. For example, part-time all wheel drive cannot be used in non-slippery conditions - you'll have to drive this car in rear-wheel drive mode, even when it is raining or snowing - in the weather conditions where all wheel drive might be needed. Second, depending on the type of all wheel drive, your car behaves differently when driving and cornering in slippery conditions. You might want to know what to expect.

Don't get confused by the abbreviations the manufacturers use: "AWD" is not necessary a full-time all wheel drive, "4WD" is not just for off-road vehicles. There is a dozen of brands the car manufacturers are using to distinguish their four-wheel drive vehicles - "quattro", "4motion", and so on. None of these actually represent the type of all wheel drive system used on the particular vehicle.

In fact, just four types of all wheel drive systems exist:

    Part-time all wheel drive

    Full-time all wheel drive

    Automatic all wheel drive

    Selectable all wheel drive

Note: On this web site, when we describe details of the all wheel drive system used on a particular vehicle, we use the definitions that are listed here.

Part-time all wheel drive

This is a "temporary" all wheel drive system. In normal driving conditions, just one axle (the rear axle normally) is driven. In slippery conditions, another axle is engaged by the driver, whether by a lever or a button. This type of all wheel drive does not have a center differential - when all wheel drive is engaged, the front and rear driveshafts are mechanically connected and rotate at the same speed.

When a vehicle is turning, the front wheels travel greater distance than the rear wheels.

Because the part-time all wheel drive system does not have a center differential, the front wheels cannot go faster than the rear wheels. This type of all wheel drive cannot be used on pavement. Turning on pavement (even on a wet pavement) with all wheel drive engaged causes transmission windup and increases the chances of the transmission breakdown. When all wheel drive is engaged, the vehicle heavily understeers and this can lead to an accident.

The all wheel drive mode should only be used on surfaces with low traction (mud, snow, ice, sand), for short periods, and at low speeds. In these conditions the transmission windup is eliminated by slipping of the wheels.

Note: "Part-time 4wd" mode of the Jeep Cherokee's SelecTrac transmission means "locking of center differential". Jeep's SelecTrac is a selectable all wheel drive system.

Full-time all wheel drive

This is a permanent all wheel drive or permanently engaged all wheel drive system. All wheels are powered at all times. The vehicles with full-time all wheel drive are equipped with a center differential that lets all wheels travel different distances while turning. This type of all wheel drive can be used both on and off road. In slippery conditions, the center differential can be locked, whether manually or automatically, depending on the vehicle.

When a manual center differential lock (available on off-road vehicles and some SUVs) is engaged, the transmission's behavior is similar to part-time all wheel drive, i.e. the front and rear driveshafts rotate at the same speed. The use of full-time all wheel drive with locked center differential is limited to surfaces with low traction.

In case of an automatic lock, a Torsen differential, viscous coupling, multi-plate hydraulic clutch, or similar traction device is used in conjunction with the center differential. When a wheel slip occurs (one driveshaft rotates faster than the other) the device locks the center differential and the torque is transferred from the axle that slips to the other axle that has traction. As soon as the wheel slip is eliminated, the device unlocks.

Some vehicles (Land Rover Discovery II, pre-xDrive BMW X5) do not have a locking center differential, but are equipped with an electronic traction control system (known as Electronic Differential Lock - EDL) on all four wheels. This electronic system detects slipping wheels by reading ABS sensors, then it applies brakes to the slipping wheels and the torque gets transferred to the wheels that have traction. While it performs well on slippery roads, the system cannot compete with a real mechanically locking differential when driving off-road.

Automatic all wheel drive

This is an "on-demand" all wheel drive system. Under normal driving conditions, only one axle is powered. When wheel slipping occurs (the driving driveshaft rotates faster than the driven driveshaft), a multiplate hydraulic clutch, viscous coupling, or other similar traction device locks and engages another axle. The torque gets transferred to another axle. As soon as the difference in the front and rear axle speeds is eliminated, the device unlocks and the vehicle goes back to the two-wheel drive mode.

The difference between the traction devices that are used in full-time all wheel drive and automatic all wheel drive systems is that the device used in automatic all wheel drive system replaces the center differential.

Advanced electronically controlled all wheel drive systems can be proactive and lock the traction device even before wheels start to slip - the need of all wheel drive is determined in real-time, based on the information that is collected from different sensors (i.e. g-force sensor, accelerator pedal position, etc.).

Some vehicles let the driver to lock the multiplate hydraulic clutch manually when the driver feels that he needs all wheel drive engaged permanently and before wheels start to slip. For example, in Nissan X-Trail, this is accomplished by pressing a button on the dashboard console. In Subaru Legacy, the clutch is locked when the automatic transmission gear shift lever is at the position "1".

Selectable all wheel drive

In this category fall Mitsubishi Pajero(Montero) with its Super Select transmission, Jeep Grand Cherokee with SelecTrac transmission, and a few other off-road vehicles. Mitsubishi, for example, has in fact a full-time all wheel drive transmission with two wheel drive possibility. In Mitsubishi, the driver can choose between the 2wd mode, 4wd mode with automatic distribution of torque via viscous coupling (acts like the full-time all wheel drive ), 4wd with locked differential (acts like the part-time all wheel drive) and 4wd with low gearing (low range part-time all wheel drive).

© www.awdwiki.com

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How Does a Tiptronic Transmission Work?

Tiptronic transmission works as an automatic and manual transmission.

Purpose

• A Tiptronic transmission is an automatic transmission that can be controlled like a manual transmission. In a standard automatic transmission, a computer selects which gear the car should operate in, but a Tiptronic transmission gives this control to the driver. The name "Tiptronic" was created by Porsche, who made the first such transmission, but it also can refer to similar transmission systems from other manufacturers.

Automatic With Manual Feel

• The purpose of the Tiptronic transmission system is to give the driver more control of the car's performance and approximate the feel of a manual transmission while keeping the car as easy to drive as an automatic. Car makers had attempted to design a manual transmission that performed like an automatic, but the Tiptronic approach was more successful.

Operation

• In ordinary driving, the Tiptronic transmission functions like an automatic transmission and can shift gears without driver control. When the driver activates the Tiptronic system, the transmission ceases to shift automatically and relies on the driver to change gears. Usually the driver controls the gears with paddle-shifters, which are small levers located on the steering wheel. One paddle shifts gear up to a higher gear, while the other shifts to a lower gear.

Driving With a Tiptronic

• Tiptronic transmission systems often feature special settings, such as a performance setting in which the automatic transmission shifts gear at higher RPMs to simulate the feeling of a sports car. Many major manufacturers use a Tiptronic transmission or a similar system in some of their models.
  
  
  

  

  
  

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Direct Injection Fouls Some Early Adopters

In their efforts to wring more power and efficiency from the internal combustion engine, automakers are increasingly turning to gasoline direct-injection technology – also known as GDI or DI. Originally developed to produce more economical and quieter combustion for diesel engines, DI is inherently more efficient and helps generate more power than port injection. And advances in engineering and engine management, fueled by fierce industry competition and consumer demand, are making DI technology more cost-effective than ever for manufacturers: gasoline DI engines are appearing in entry-level models from Ford Motor Co., General Motors Co.’s Chevrolet and Hyundai Motors. Currently, more than 60 2011 and 2012 models in the U.S. offer DI engines as standard equipment.

But there has been a dark side to the technology: carbon build-up around intake valves that, over time, can degrade power and efficiency, eroding the bonus DI is supposed to provide. While there’s evidence that the most recent designs and technical enhancements have greatly reduced the issue, carbon buildup has been a distinct and well-documented issue in some DI engines from a variety of manufacturers over the last few years.

Known Problems

A U.S. patent application filed in 2002 by Volkswagen AG explains the DI-engine carbon-deposit dilemma this way: “Gasoline engines with direct injection of the fuel into the combustion chamber…suffer especially from the problem of the formation of carbon deposits…especially in the neck region of the intake valves.”

The document describes these deposits as a sticky coating of oil and fuel constituents that, once formed, serves as a base for further deposits, creating “a circular process, by which the coating thickness of the carbon deposits continuously increases.” Excessive carbon deposits “have extremely negative effects,” the patent application concludes, citing significant performance losses, sporadic ignition failures and, potentially, holes burned in the structure of the catalytic converter (should bits of carbon break from the valves and pass though the combustion chamber).

Ameer Haider, GM’s assistant chief engineer for V6 engines, certainly knows the problem, tellingAutoObserver, “DI engines are prone to forming oily deposits on the intake valves, unlike in port fuel-injected engines, where a constant spray of fuel into the port allows any deposits to wash away. With DI engines, the fuel gets injected directly into the combustion chamber, so there isn't a chance for the deposits to wash away. Typically, deposits form when soot – which is an end-product of combustion – adheres to the valve stem.”

The main purpose of VW’s patent application was to propose a fix for DI engine carbon deposits: specifically, applying “a catalytic surface” to the engine valves that “counteracts the formation of carbon deposits.” But nearly 10 years later, there’s ample evidence that this and other potential solutions have failed.

Constantine Boyadjiev works as a risk management officer at a financial firm in New York and has been an auto enthusiast for most of his life. In 2008, he decided it was time to part with his beloved 2001 BMW M5, mainly due to escalating maintenance costs – but also because he discovered that a number of fellow owners were dealing with expensive-to-fix carbon build-up in their vehicles’ engine cylinder heads.

When Boyadjiev replaced his BMW with a barely-used 2008 Audi RS 4, he thought he had put all worry about carbon build-up behind him. But, as he said, “Little did I know that there was a much uglier carbon-build-up problem awaiting me.” Boyadjiev became involved with the online RS 4 owner community when he was searching for his car, in particular a group of veteran Audiworld.com members who later migrated to QuattroWorld.com. He kept active with the group as he took delivery of the car and enjoyed the first few months of ownership. Not long after, though, he was dismayed to see that “the message boards caught fire with plenty of formally documented cases” of carbon build-up with fellow RS 4 owners’ engines.

Boyadjiev admits to some initial “wishful thinking” that perhaps the problem might only affect earlier production models or that the forum members were merely trumpeting an isolated issue. But then, despite his own “religious” maintenance practices, including using only 93-octane premium fuel and avoiding short, in-town trips that failed to bring the engine up to proper operating temperatures, it soon was apparent his Audi’s 4.2-liter direct-injected V8 also was plagued by carbon buildup.

“The loss of performance became very noticeable over time,” he says. He decided to document it, taking the car to a local automotive performance specialist in nearby Stamford, Connecticut, to have its power measured by a dynamometer.

At its first measurement, Boyadjiev’s RS 4 had 15,000 miles and produced 324 all-wheel horsepower, measured at the wheels (AWHP). Roughly one year and 5,000 miles later, the same test showed 317 AWHP. After another year and 5,000 miles, power was down to 305 AWHP. Power from the 4.2-liter V8 had degraded by almost 5 percent in just 10,000 miles.

Considering the RS 4’s performance pedigree – and correspondingly large price tag (in excess of $70,000 MSRP) – this was an alarming trend, something Boyadjiev thought Audi would want to address head-on, especially since parent company VW had earlier documented these very issues in its DI engines. But Boyadjiev and his fellow RS 4 owners found Audi quick to dismiss the issue as a byproduct of poor-quality U.S. gasoline and American-style driving habits (i.e. the absence of high-speed runs on the Autobahn). Audi offered no assistance.

So Boyadjiev took an action to which many other RS 4 owners already had resigned themselves: he had an independent mechanic disassemble the engine and clean it – a $1,200 expense at the time. He returned to the dynamometer to see if the cleaning had made any difference. It had. Engine output soared by 41 AWHP and the car felt new again. For the moment, at least.

Boyadjiev said he is prepared to pay for such a maintenance cleaning every 10,000 miles. And while he is certainly not happy about that, he’s willing to endure the hassle and cost. “The car is so rewarding and a joy to drive,” he says. He is far less complimentary about Audi’s response to the issue. Despite the evidence Boyadjiev and many of his fellow RS 4 forum members have presented, “the company continues to deny this is a very serious issue,” he said. “I have very little respect for a company that refuses to stand behind its name, especially when professing a motto of ‘Progress through Technology,’” he added. And experiences like Boyadjiev’s are not uncommon.

A Google search for “direct injection carbon build up” reveals a flood of owner complaints about the issue across vehicle brands and models, including particularly active threads for the VW GTI, the Lexus IS 250, and a variety of Audi models in addition to the RS 4.

All Engines Not Designed Equally

Many automakers’ gasoline DI engines do not appear to exhibit any carbon build-up issues at all, however. Digging into online threads about Cadillac’s 3.6-liter DI V6 in its popular CTS lineup does reveal some owner concerns about carbon build-up, but it’s difficult to find even a single report that any build-up has actually occurred – a record that is notable considering that Cadillac has sold more than 200,000 CTS models with DI V6s (Audi sold fewer than 2,000 RS 4s in the US during its two-year sales run).

Haider, GM’s V6 assistant chief engineer, explained how GM has designed its DI engines to combat carbon buildup: “We maintain great engine function and performance in our all our DI engines through an optimization strategy with our valve events,” he said. “Our intake-cam timing, injector targeting and timing of the injection events are optimized to avoid direct fuel contact on the intake valves. This strategy keeps smoke and soot formation to an absolute minimum, which in turn prevents excessive deposit formation.”

At the Detroit Auto Show in January, Ford was confident enough about its popular 3.5 liter EcoBoost direct-injection V6 to have technicians tear down an example engine that had accumulated the equivalent of 160,000 miles through an intentionally abusive regimen of log dragging, high-speed towing and desert racing. When they opened it up before a live audience, they found some light carbon deposits on the valves and pistons, but not enough to affect performance. In fact, the engine showed a loss of just one horsepower afterwards – roughly what Boyadjiev’s RS 4 engine lost every 500 miles.

Stephen Russ, technical leader for combustion for Ford’s 2-liter Duratec DI engine, said that similar to GM, engineers have determined the proper injection-timing calibration to help eliminate the carbon deposits. But Russ also said the technology of injection components – particularly the high-pressure solenoid injectors – has quickly matured, meaning excess valve deposits in most DI engines should become a thing of the past as these improved components are incorporated into production.

Tony Chick, principal engineer at European Performance Labs in Stratford, Connecticut, has made a career of repairing and rebuilding high-performance engines from Audi, Porsche AG and BMW, among others and his operation has garnered a reputation among car enthusiasts as a go-to place for cleaning DI engines that have become choked with carbon. Chick thinks the problem for most affected engines can be traced to the breathing system – specifically, the design of its crankcase ventilation and exhaust-gas recirculation components.

All modern gasoline engines return some crankcase and exhaust gases back through the intake manifold in order to help control emissions, but, according to Chick, some exhaust-gas recirculation designs are “dirtier" than others. Some, he said, are less-effective at preventing the passage of tiny bits of oil, carbon and other particulates that eventually get baked onto the intake ports and valves.

Chick reached his conclusion after inspecting dozens of different DI engines at his shop and finding some, like the V8 in Boyadjiev’s Audi RS 4, regularly choked with carbon while others, like the DI version of Porsche’s horizontally opposed 6-cylinder, remained much cleaner.

If he’s right, the rapid adoption of DI has actually illuminated an issue, not caused one. A “dirty” intake or exhaust-recirculation design can easily go undetected in a conventional port-injected engine due to the cleaning effect of gasoline passing over the intake valves. When the same engine designs are adapted to direct-injection fueling, however, that cleaning effect is suddenly lost – and the carbon layers can build.

There is no simple fix for engines that are prone to carbon build-up, Chick says. What’s needed is a complete redesign of the crankcase ventilation and exhaust-gas recirculation systems to prevent particulates from getting through. Fortunately, the manufacturers whose engines are frequently cited in carbon build-up reports – mainly VW, Audi and Lexus – appear to have taken this step with many of their latest models. For instance, Audi’s new 3-liter supercharged V6, used in the S4 and A6 models, has so far been free from carbon-related complaints – a far cry from the 3.2 liter V6, which has numerous threads dedicated to the condition.

If Ford and GM engineers and Chick are correct, the carbon-buildup problem now may be relegated to previous engine designs that were not well-adapted for DI. But that’s probably little consolation to some early adopters like Boyadjiev, who must add regular carbon cleaning services to their cars’ ongoing maintenance requirements – a cost that, for now at least, they are expected to absorb entirely on their own as they grapple with the “dirty” secret of this emerging technology.

Mark Holthoff manages customer support for Edmunds.com.
Matt Landish oversees digital media development and publishing for Edmunds.com.

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