Thursday, April 28, 2011
2012 Nissan Versa Seda, Nissan Leaf NISMO RC Concept Make World Debuts at New York International Auto Show
Tuesday, April 19, 2011
Driven to Distraction
The MyFord Touch control and display system includes LCD screens that flank the speedometer and a screen in the center stack.
We live in a touch-screen world. Just ask the designers of the iPhone, iPad or any Android device, and they'll tell you there is no better way of putting a near-infinite amount of information and control within a defined space than on a screen that you can interact with directly. Automakers have been integrating touch-screen interfaces into dashboards for several years now, digitizing the controls for everything from navigation to climate-control systems onto large console-mounted screens with an ever-increasing architecture of menus and submenus that now rival the complexity of desktop PCs.
Take the new $58,000 Hyundai Equus, for instance. It not only has an 8-inch screen in the console for everything from navigation to climate control to camera-based parking guidance, the car also comes with its owner's manual installed as an application on an included iPad.
What's driving the need for in-car screens? "Computerization and wireless technology have greatly increased the range of entertainment options," says John D. Lee, a human-factors expert at the University of Wisconsin-Madison. New cars have satellite radio and Bluetooth links to cell phones, they can play MP3s and read text messages, and many of their computer-controlled systems can be customized by the user. "Screen-based systems make it possible to dramatically increase the number of functions and features available to the driver," Lee says. "Presented as individual knobs and buttons, they would likely exceed the space within arm's length of the driver."
Sounds ideal, right? Not so much.
It's no coincidence that the high-tech feature creep that has necessitated the in-car LCD screen has evolved concurrently with a new concern about the dangers of distracted driving. So far, most distraction-related accidents have resulted from drivers taking their eyes off the road to dial or answer cell-phones, or from the relatively new, boneheaded phenomenon of texting while driving. The statistics are chilling: The National Highway Traffic Safety Administration reports that 5,474 people were killed and an estimated 448,000 were injured in distracted-driving accidents in 2009. According to the Insurance for Highway Safety, drivers who use handheld devices are four times as likely to get into serious crashes.
Part of the rationale for integrating a wide range of entertainment and telecommunications devices into a vehicle's controls is to deal with the fact that, like it or not, drivers are bringing phones and iPods and various texting devices into their cars. It would seem better for them to hunt for a song or a phone number on a custom-designed 8-inch console screen than to fumble around for those things on the tiny screen of a portable device. Yet as the complexity of a car's operating system has grown, it seems that the auto industry may be learning all the wrong design lessions from gadgets that they are trying so hard to accommodate.
The Problem
Recently, Consumer Reports slammed the MyFord Touch system, which is at the forefront of a new generation of advanced automotive computer interfaces. Ford had previously gained accolades from auto journalists and customers alike for its Sync system, a voice-recognition technology launched in 2007 that allows drivers to control many of a car's functions with voice commands. Voice recogntion has long been considered a holy grail for automotive interfaces, since it theoretically allows drivers to control complex systems without taking their eyes off the road.
Synch resulted from a partership between Ford and Microsoft (MSN Auto's parent company), and its voice recognition was good enough to call up names from the driver's cell-phone contact list, and even to find individual songs and artists by name on an iPod. The new MyFord Touch system - also known as MyLincoln Touch in the new Lincoln MKX - expands on the voice control with one 8-inch touch-screen and capacitive slide controls built into the center console, plus two 4.2-inch screens integrated into the instrument cluster and a series of steering-wheel-mounted multidirectional control pads.
Ford says the system "helps you keep your eyes on the road," but Consumer Reports' senior automotive engineer Thomas Mutchler thought otherwise, calling the system so complicated that it could become a distraction while driving. "The basic idea's OK," Mutchler says. "There's nothing wrong with having multiple ways of making an input. If you have four ways of adjusting climate control, that's fine, but at least one of them should be a good one. The touch-screen and the buttons are small, and it's hard to find the one you want to push."
He then fired off a litany of ergonomic crimes: "The touch-sensitive capacitive switches are finicky and don't work well when it's cold. The steering-wheel comands are menu-driven, so you have to go through a couple of steps to do something that could have been done with the turn of a knob. The voice commands work sometimes and they don't work sometimes, and you feel kind of stupid talking to the car when there's someone else in the car with you."
It's a pretty strong indictment: The system that was supposed to be designed to help you manage complexity so that you don't get distracted ends up being so complex that it becomes the distraction. As you might expect, Ford sees things differently. A spokesman says the system provides a "smarter, safer, simpler way to connect drivers with many in-car technologies and their digital lives." He said that customer feedback on the system has been positive, but that Ford takes feedback from both customers and Consumer Reports seriously when it comes to upgrading and improving the system. Indeed, as software-based operating systems, Sync and MyFord Touch can be updated relatively easily, and some upgrades to the system have already been made.
The 2011 Audi A8's MMI system features a new touch-pad. It's designed for easy interaction, so the driver doesn't have to take his or her eyes off the road for long.
It's Not Just Sync
Ford is hardly the only manufacturer that has had to defend itself against criticism over distracted driving. Just last year, Audi engineers were surprised and shocked after The New York Times ran a picture of the manufacturer's MMI Touch system, which had just been unveiled at the 2010 Consumer Electronics Show, under the headline "Driven to Distraction." One Audi engineer said that the system had been designed specifically to mitigate the distracting influence of smart phones, MP3 players and other devices, and that any suggestion that a motorist would stop using these devices if cars stopped integrating their functionality was naive.
Whether it is a good idea in the first place to build "infotainment" systems into vehicles will probably remain an open debate for some time, yet the "complexity and confusion" issue is surely made worse by the fact that every manufacturer has its own take on how the technology should be implemented, guaranteeing almost zero standardization.
Audi's MMI system in the A8 has a touch pad that can be reconfigured digitally and that can interpret finger gestures. Mercedes-Benz's Comand system has a dialing puck and an optional dual-view screen that lets passengers and drivers see different things. Lexus has a center-console-mounted Remote Touch mouse with force feedback to enter commands on the screen. And these interfaces are by no means consistent with a brand; some cars have basic touch-screens, others have pucks, dials or multidirectional buttons. Almost all manufacturers have some sort of voice control, but commands are so varied that drivers can end up calling out a thesaurus-worth of synonyms - "Heat!" "Temperature up!" "Warm!" "I'm freakin' cold, turn on the heater!" - just to get anything done.
It Isn't Going Away
Regulators and safety advocates would certainly like to see most of this technology removed from the driving experience. But most automotive experts agree that screen and voice-control systems are here to stay. There are guidelines for good interactive system design; the Alliance of Automobile Manufacturers published a 90-page document outlining the best practices for the industry in 2006. It's long-winded and a bit dated, but Lee of the University of Wisconsin-Madison summarizes the basic wisdom of the document in a few points:
- Complex displays that require the driver to search for information using glances longer than two seconds should be avoided.
- The interaction should not "time out" or force the driver to attend continually to the task. The driver should be able to interrupt the task easily and return attention to the road.
- Visual information should be placed near the driver's line of sight.
- The display should be easily readable with text and icons that can be seen at a glance.
Sounds simple, right? But the guidelines are voluntary. Even NHTSA, which is working on its own guidelines, isn't planning on forcing automakers to build their systems to any particular standard.
In the meantime, it seems that confusing systems are the inevitable growing pains of an industry stumbling to find its footing in the fast-moving world of information technology. Despite his concerns about Consumer Reports' criticisms of MyFord Touch, Mutchler sees plenty of room for hope about touch-screens.
"Ford's problem isn't one of ambition, it's one of execution," he says, pointing out that the Toyota Highlander and Chrysler's new UConnect system use large touch-screens with simple menu structures. "Everyone's going to go to this sort of system eventually. Research has shown that touch-screens are more intuitive to use. The next step is the one that quite a few researchers are worried about. What's the impact of a constant flow of Facebook updates or text messages being read to you constantly and you wanting to respond to them constantly? I don't think there's a great answer yet on how you can respond to that cognitive load and still drive a car."
Sam Foley is a Connecticut-based automotive journalist who has written for GQ, Forbes, USA Today, the New York Post and various other publications.
Tell us what you think of the digitizing of cars, helpful or distracting?
Friday, April 1, 2011
First Test: 2011 Nissan 370Z Touring
A Dollar-Per-Grin Win
By Nate Martinez
At Nearly $42,000, a fully loaded 2011 Nissan 370Z Touring isn't cheap-in fact, the car is pricey enough to merit a mild case of sticker shock. But upon closer inspection of its expansive spec sheet, followed by a multi-day test drive, the shock fades while the athletic coupe's intrinsic value grows.
Consider the 370Z's impressive attributes. There are the 14-inch front, 13.8-inch rear Akebono brakes that haul the 3362-pound Z to a stop from 60 mph in only 102 feet (a BMW M3 Coupe with Competition Package does it in 110 feet, a GT-R in 101 feet). These massive four-piston front, two-piston rear binders clamp hard on Nismo's optional $580 R-Tune performance brake pads designed to withstand temperatures of up to 700 degrees Fahrenheit. This is the quickest-stopping Z we've ever driven. And we've driven many, many Zs over the years.
There are the featherweight 19-inch aluminum wheels forged by Japan's renowned Rays Engineering, a supplier of the AT&T Williams Formula 1 team. Even now, only a handful of six-figure supercars roll on such fancy footwear. The rims, along with adhesive Bridgestone Potenza RE050A rubber, a taut suspension setup, and a vicious limited slip differential (all part of the Sport Package), help the 370Z Touring attain a 1.01 g average on the skidpad. That's slightly stickier than a mid-engine, no-option $60,000 Porsche Boxster S at 1.0 g, mind you.
Straight line acceleration adds to its value. The 3.7-liter V-6's 332 horses and 270 pound-feet of torque send the Z to 60 mph in 4.9 seconds, while a quarter-mile passes in 13.4 seconds at 105.2 mph. A rocket it isn't, yet for the segment it occupies, the stats aren't disappointing.
Although you'll have to cough up the Sport Packages $3,030 entry fee to attain such laudable performance, every dollar is money well spent. The option group includes "zero-lift" front and rear spoilers that cut the Z's drag coefficient to a slim 0.29 Cd from the standard car's 0.30 Cd, and though you'll never feel the 0.01 difference in Cd, you will have gained some pub fodder.
The Navigation Package with nearly every facet of multimedia is also worthy of its $2,150 price. The 7-inch VGA monitor is a capable navigation screen and serves as a DVD movie screen when the car is parked (but really who watches DVDs in a parking lot?). A Bose-supplied stereo comes with an iPod input, 9.3-gigabyte hard drive, and streaming Bluetooth capability. Of course, you can connect your mobile phone via Bluetooth, too, though the sound quality and connection strength was patchy.
One of the best new-for-2011 amenities is the rearview camera, which eases any skittishness when reversing. It is included in the Navigation Package, but if you don't opt for the group, you can still get a standalone $750 in-mirror monitor.
The 2011 model year also brings the 370Z Roadster's synthetic suede door and seat inserts to the coupe. The soft, cozy material gives the comfortable, attractive cabin a higher-quality feeling. Leather-wrapped electronically adjustable seats remain standard in the top-level Touring, and support your bum and back with cushioning.
After driving the 2009 370Z three years ago, editor-at-large Ron Kiino had this to say about the then-new car's handling: "The most alluring aspect of the new Z is the sense it imparts: It feels sharp, direct, and balanced, a well-honed santoku knife to the 350Z's blunter and bulkier cleaver."
Kiino's observations still hold true for the 2011. The Z sticks hard and goes fast, and with the center console knee pads and supportive seats, you're always set in the proper position to command its athletic moves. The process usually goes like this: Following an electronically orchestrated downshift or two will help from the controversial SynchroRev Match (the technology's fun factor wilts the longer it's used), the car's inner santoku knife takes over, allowing you to play IronChef with delicious pieces of hot pavement. Dab the Akebonos, mash the floor-mounted accelerator, and prepare for a stupid grin to be plastered on your face.
Santoku sheathed, the Z rides firm, as expected, yet it is not overly jarring. The main source of in-cabin din are the massive 245/40R-19 front, 275/35R-19 rear Bridgestones. Compared to our long-term 370Z Roadster, the coupe serves as the ideal long-distance tourer by virtues of side visibility, overall civility, and cabin quietness.
Getting what you pay for isn't a problem in the 370Z Touring. After three years, we continue to admire its comfort level, style, and, of course, performance. In an automotive world filled with expensive sports cars touting questionable bang-for-your buck returns, the Z carries on as one of the best values around, especially in the dollar-per-grin category.
Friday, March 18, 2011
Tuesday, March 15, 2011
Are Our Cars Making Us Lazy?
By Sam Foley of MSN Autos
While automated features are nothing new on the automotive landscape, some believe we have gone too far, too fast.
In 1940, the now defunct American carmaker Packard introduced its ultraluxurious 180 Series touring sedan with a minuscule feature that would change the automotive landscape forever. The company outfitted the posh 4-door with powered windows rather than a standard crank-driven system - push a button, the window went down; push it again, the window went up.
This feature was a marvel of engineering. It was also probably the first completely frivolous auto amenity. But more importantly, it sparked the development of hundreds of automated systems - electromechanical or, more recently, digital - designed to handle tasks that motorists could otherwise do for themselves.
By the mid-1940s, power windows were everywhere, next seen on Ford Lincoln Custom limousines, then shortly after in Cadillacs, followed by Buicks and so on. Before the end of the decade, power seats made their debut, and power steering arrived in the early 1950s.
In 1957, Cadillac introduced the most automated automobile of its time: the Brougham. A limited-edition version of the Cadillac Eldorado, the Brougham was designed to be the most luxurious car in the world. It was assembled by hand; came with slick, rear-facing "suicide" doors; and had a list of "world first" features, such as an automatic starter, a transistor radio, memory seats and a trunk that opened and closed with the push of a button.
While the Brougham's feature list was impressive, it left many driving purists wondering: Are all of these technologies designed to make driving more pleasurable really necessary, or are they just making us lazier drivers? This sentiment is gaining momentum once again in today's high-tech automotive world - and not just from driving enthusiasts.
The downside of Automation
As incredible as the Brougham was back in the day, modern vehicles such as the Lexus LS 460 put it to shame in terms of available high-tech bells and whistles. An optioned-up LS 460 can have rain-sensing automatic wipers, an auto-closing trunk lid, auto-adjusting high beams, power windows and sunshades, power door closures, a voice-controlled GPS navigation system, an electronically controlled braking system that overrides simultaneous gas- and brake-pedal application, and an automated system that will parallel-park the car for you.
These features are not just the province of the luxury-vehicle segment anymore. The 2011 Chrysler Town & Country minivan can be outfitted with a power liftgate, dual power side doors and power-folding third-row seats, as well as the usual complement of power front seats, power mirrors and electrochromic dimming mirrors. Push all the buttons at once, and the vehicle's dozens of motors whir and buzz in a battery-straining ballet, letting the kids spill out the sides unsupervised while the groceries dump out the back and into the driveway.
While all of these features are meant to be helping hands, their benefits often blind motorists to their drawbacks. And it's definitely worth considering exactly what all this automation is doing to us as drivers.
As it turns out, automated systems can cause some pretty distressing problems. For instance, power windows have long been recognized as a child safety hazard. A 2004 National Highway Traffic Safety Administration study estimated that power windows killed an average of five children per year. Regulators have now required that all vehicles from the 2008 model year forward use automatic window controls that are less likely to be triggered by children.
And there is a cultural issue at stake as well: the loss of skills that occurs when humans voluntarily abdicate responsibility to machines. Consider the breakdown of navigational skills due to our reliance on GPS devices. Many people no longer pay attention to landmarks and other geographic indicators as they drive, and the skill of map reading is fading as well.
Even some proven safety systems have drawbacks. Performance-driving enthusiasts have long held a low opinion of stability-control systems. They believe that because the technology saves bad drivers from their own mistakes, they are more likely to drive beyond their abilities.
"The performance community is always going to have a backlash against technology; that's just their personality," says Christopher Nowakowski, a human factors researcher at California PATH at the University of California at Berkeley. Nowakowski allows that crash data suggest that stability control does save lives. Nevertheless, he says the data don't measure the influence of sloppy, overconfident drivers on other people's accidents.
The Lexus LS 460 can can be outfitted with rain-sensing automatic wipers, an auto-closing trunk lid, power door closers, a voice-controlled GPS navigation system, and an automated system that will literally parallel-park the car for you.
Driving on Faith
Nowakowski is keenly aware of how automated driving is becoming, and of the impact of technology on human behavior. "These types of systems can be beneficial, but the more automation you have, the more you can lull people into a false sense of security," he says. And research done by California PATH shows that drivers are willing to invest a surprising amount of faith in automated systems.
Nowakowski and his colleagues tested a highly sophisticated Nissan adaptive system that used both lidar (light detection and ranging) and vehicle-to-vehicle wireless communication to allow one car to follow another at surprisingly tight distances. "We're told that we're supposed to keep two seconds of distance between us and the car in front of us at highway speeds," he says, "but no one really does that; the gap is closer to 1.6 seconds for most drivers. But with this system, we found that people were perfectly willing to accept the vehicle following the car ahead of it with only a 0.6-second gap."
Human Handlers
Advanced automotive automation technologies aren't just cruising around on academic test tracks. Earlier this year, Google researchers began driving fully autonomous cars on public roads to test the real-world readiness of the technology. The cars had human handlers at the wheel to make sure that none of their vehicles' mistakes turned lethal, and by all accounts, the vehicles performed well. Nevertheless, researchers such as Nowakowski have concerns about what could happen if such technology is commercialized.
"As you start to get vehicles that are highly automated, ones that can steer themselves and maintain speed and make turning decisions, what are you doing as a driver?" he asks. "Obviously you're going to start texting and doing whatever will keep your attention level up, because you don't want to just sit there and watch what the car's doing. We know this is a problem with airline pilots that have highly automated planes, and their job is to sit there for eight hours and watch a bunch of numbers that don't move; we know they don't do this very well." (This phenomenon was made tragically clear in February 2009, when the sleep-deprived pilot of Colgan Air Flight 3407 failed to react to the signs of icing on his plane while it was on autopilot. The resulting crash killed all 49 people abroad.)
Plus, as anyone who's ever seen his computer unexpectedly freeze knows that technology is only as good as the people who make it. This was shown spectacularly at a press demonstration of Volvo's pedestrian-avoidance technology earlier this year. The system is designed to apply full braking power automatically whenever an equipped vehicle's camera and radar sensors detect a pedestrian. Unfortunately, the system apparently didn't like the Swedish automaker's test dummies, as it plowed right into them in three out of 12 test runs. The company claimed that the dummies weren't set up properly. Obviously, such a system is meant as a fail-safe to human judgement and reaction, but it served as a compelling demonstration that, no matter how sophisticated the automation technology, if you act like a dummy, someone's probably going to get hurt.
Friday, March 4, 2011
'Idiot' Enlightenment
Tuesday, March 1, 2011
Thursday, February 17, 2011
Bring a Wingman When You Buy a Car
Tuesday, January 25, 2011
Technology for Winter Driving
Let's say your looking for a new car. If you've never had to pry a wiper loose from a frozen windshield, you might not recognize the comfort and safety challenges that confront motorists in harsh winter climates. If you live in a colder clime, you do know the horror of losing sensation in your fingers and toes or sliding haplessly into a ditch. Either way, make sure your new car has some of these features to make life in snow country a lot easier.
Antilock braking systems are good for all seasons. They keep your car under control during braking by preventing the wheels from locking and skidding. ABS shortens stopping distances in most cases, but its main purpose is to allow steering, even when you are in a panic stop.
Traction Control
Where antilock brakes help you stop on slippery surfaces, traction control helps you accelerate. It detects when your drive wheels are slipping and reduces engine power and/or applies the ABS to keep power going to the wheel that has traction. While traction control has helped make rear-wheel-drive cars more viable in snow, some systems are so conservative that they keep you from gaining speed on loose snow and may need to be switched off. The most advanced traction control is better at reacting optimally for any given road surface.
Electronic Stability System
Electronic stability systems are known by countless names, usually including the word stability. What they do is sense the car's direction, compare that to where the driver is steering and apply individual ABS brakes to steer the car back on its intended course. One of the most significant auto safety advancements in history, stability control is especially useful in snow, where it can prevent fishtailing. Though expensive, it can pay for itself by preventing a single fender bender.
Four-/All-Wheel Drive
The need for four-wheel drive for urban dwellers is probably overstated these days, but it certainly can't hurt, especially in wintery regions that have hills and/or poor snow removal. Heavy-duty four-wheel drive is often overkill; all-wheel drive, which is lighter and cheaper, is totally automatic and may be more effective.
Too many sports-car owners learn too late that all-wheel drive can only do so much in a car that hugs the ground. Throw in a set of summer tires and you're really going nowhere - at least nowhere you want to go. In deeper snow, SUVs and higher-riding sport wagons rule the road.
All-Season or Winter Tires
The importance of tires can't be overstated, especially in winter conditions. While modern "winter" (no longer "snow") tires are exceptional on snow and particularly ice, they may suffer from extended stopping distances and diminished traction when it's dry or warm. Good all-season tires are an excellent compromise for people who don't need - or can't justify - a second set of tires and the hassle and expense of storing and swapping them twice a year. That said, don't use summer performance tires in the snow. Designed for the opposite conditions, they're no less than a safety hazard on cold, snowy or icy surfaces.
Winter Transmission Modes
Some vehicles with automatic transmissions have a special Winter mode that helps prevent slippage when accelerating (with or without traction control as a backup). They typically make the car accelerate starting in 2nd gear rather than 1st, then upshift as promptly as possible through higher gears. It may sound odd, but higher gears diminish thrust at the drive wheels, unless the engine is revving fast. Less force equals less slippage. Some automatics with manual-shifting modes let you start off in 2nd or 3rd gear to achieve the same effect.
Heated Seats, Steering Wheel
With leather upholstery in particular, heated seats are a must. One benefit is that they warm before the car's heat begins to flow. Offered mainly in front seats, the best give you several heat settings, but the most common is a high-low switch. In some cars, they're only fully on or off, but that's better than nothing. Relatively new are heated steering wheels, which solve the Hobson's choice of discomfort versus hazard - a freezing steering wheel or trying to steer with gloved hands.
Heated Side Mirrors
More common than ever, heated side mirrors can clear themselves of fog, melt accumulated ice or prevent further snow buildup. Many cars activate them along with the rear defogger, while some have their own dedicated button and a few are connected to the heated-seat switch.
Headlight Washer/Wipers
The little wipers you may have seen on luxury car headlights might seem extravagant, but they serve to clear grime, road salt and snow accumulation that can dim your headlights. Most cars that offer headlight clearing use washer jets alone, which have proven effective. Because the jets typically emerge from the bumper, spray then retreat, the feature is more stealth - and more common - than you might know. Some cars spray the headlights at the same time are the windshield is the headlights are on. Others have buttons that let you wash the headlights whenever you wish.
Heated Windshield
Though this feature is rare, some windshields are coated or impregnated with a thin film or fine wire grid that heats the glass itself, melting ice or loosening it in sheets. A shortcoming of the wire type is the exaggerated headlight glare that may take on a starburst shape.
Heated Wipers and Washers
A wiper de-icer, also known as a heated wiper park, frees wipers that are frozen to the glass where they rest, or "park." It also aims to keep the blades pliable enough that they contact the windshield over their full arc. Applied to windshield and/or rear-window wipers, the technology may be an option with its own button or a standard feature that works automatically in cold weather or along with defrosters. Heated nozzles and/or hoses and reservoirs serve to keep windshield washer fluid flowing in cold temperatures. It may help melt or clear ice, but mainly the feature should prevent the fluid from freezing once it lands on a cold windshield.
Remote Start
Most of the more esoteric winter-oriented features came along to alleviate the problems of a cold car. Here is where a remote start is a godsend. A warm cabin and clear windows make seat, steering wheel and supplemental window heaters a luxury instead of a necessity. A warm engine compartment can prevent wiper fluid freezing. The best remote-start systems automatically turn on the heat, defrosters and seats. Remote start isn't the most environmentally friendly feature, but it beats scraping ice in the frigid wind.
Retractable Hardtop (Convertibles)
People who have foregone convertibles due to their wintertime shortcomings have more choices than ever, thanks to the explosion of retractable - hardtop models. They're just like non-convertible cars when their tops are up. Why haven't you seen many? You probably have; you just didn't know it.
Block Heater
Compared to 20 years ago, cars today start almost flawlessly in cold weather. That said, there's cold ... and then there's cold. In the Northern states, where the temps often drop below zero and stay there, even the best-engineered cars need a hand. Block heaters that plug into a household electric outlet (typically overnight) keep the engine block warm (which keeps the oil thin), making starting easier and reducing wear and pollution. Electric dipsticks, battery warmers and other solutions are available as aftermarket products, but when a factory option is offered it's usually a heater that screws into the engine block or bisects a heater hose, where it warms and circulates the engine coolant.