2014 Mercedes-Benz E250 BlueTec review: Brilliant BlueTec Benz's only flaw is dashboard tech

Pricing Unavailable
  • Available Engine Diesel
  • Body style sedan

Roadshow Editors' Rating

7.6 Overall
  • Performance 8
  • Features 8
  • Design 8
  • Media 6

The Good The 2014 Mercedes-Benz E250 BlueTec's turbodiesel power-plant delivers an exceptionally good blend of smooth, confident performance and thrifty fuel economy. The vehicle feels luxurious enough to justify its price tag and the available safety tech impressed.

The Bad Dated, confusing COMAND infotainment is in need of a redesign. Mercedes-Benz apps are sluggish and nearly unusable. Tiny, hidden prompts for the optional parallel parking assistant make the otherwise great system difficult to use.

The Bottom Line The powerful, efficient 2014 Mercedes-Benz E250 BlueTec is a great car -- nearly the total package -- but it won't be a great "tech car" until its dashboard tech gets a much needed overhaul.

I'll cut to the chase. The 2014 Mercedes-Benz E250 BlueTec is brilliant and it mostly has its engine to thank for it.

Under the hood, you'll find a relatively small (for a vehicle of this size) 2.1-liter twin-turbodiesel four-cylinder. Output is stated at 195 horsepower, which is decent when compared to the similarly-sized Honda Accord's 185 ponies from its 2.4-liter engine. With a relatively low redline, it's no surprise that high-revving horsepower isn't the diesel's strong suit, so we instead turn our attention to the stated 369 pound-feet of torque, which is impressive no matter how you slice it.

That engine is mated to seven-speed automatic transmission, the only gearbox option for the E250 BlueTec, which then sends power to the rear wheels. Drivers can option Mercedes' 4Matic all-wheel-drive system, which should slightly improve sure-footedness in slippery conditions, but the rear-wheel-drive configuration is certainly the more fuel-efficient of the two configurations. And fuel efficiency is indeed one of this power train's strongest features.

The diesel-powered E250 BlueTec matches 369 pound-feet of torque with up to 45 mpg highway.

Antuan Goodwin/CNET

According to the EPA, the rear-driven variant of the E250 BlueTec is good for 28 mpg in the city, a very decent 45 mpg on the highway, and 34 mpg combined. The 4Matic equipped model drops down to 27 mpg and 42 mpg in the city and on the highway, respectively.

Also helping fuel economy is an auto stop-start system that shuts down the engine while the vehicle is stopped (say, at a traffic light) to reduce fuel wasted to idling. I found the system to be smooth and unobtrusive and I appreciated the extra quietness of the cabin while stopped. By the time I could casually get my foot from the brake pedal to the accelerator, the Benz was fired up and ready to roll. If you're more of a lead footed driver, the system is easily defeated with the press of a dashboard button.

My actual numbers for testing were a bit lower than the 34 mpg combined estimate, likely due to a variety of reasons: I spent a lot of time testing the driver aid tech in heavy traffic; the vehicle spent hours idling while we produced the video at the top of this review; and I couldn't help matting the accelerator more often than was absolutely necessary to sample the torquey diesel performance.

Driven like a sane person, the E250 BlueTec was remarkably comfortable. The diesel engine was very quiet, the shifts of the seven-speed automatic were imperceptibly smooth, and the suspension was supple, even with the no-cost upgrade to the Sport package's sport-tuned suspension. The ride wasn't so supple that you wouldn't notice the bumps in the road or rough patches of asphalt, but I was never jarred by the bumps, and the ride was never harsh.

2.1L BlueTec engine

The smooth delivery of the twin-turbodiesel's force makes it ideal for this grand tourer.

Antuan Goodwin/CNET

With so much torque available from quite low in the tachometer's sweep, the engine was both responsive and effortless. When I needed a bit more grunt to make a pass, there was no need to wait for the transmission to downshift, the acceleration was nearly instantaneous and linear.

Asking for a dramatic change in velocity -- say, stabbing the accelerator when cruising at 25 mph -- isn't nearly as instantaneous. Turbo lag, while slight and only momentary, is noticeable and the smoothness of the transmission's shifts becomes a liability where snappiness is concerned. But there's the slight whistle of the turbos spinning and the steady press of acceleration on the other side of this brief hesitation, which makes it worth a moment's patience.

Even with the torque going to the rear axle and the Sport package's suspension and appearance upgrades, the E250 BlueTec is no sports car. It's more of a powerful Grand Tourer, much more comfortable on the highway where its high-speed stability and supple suspension can do their thing.

Dated dashboard tech
I'll also cut to the chase where the Benz' dashboard tech is concerned: The COMAND infotainment system is terrible, probably the worst in class at this point. I won't belabor the point, because we've been down this road many times before, but the system's weird three-tiered organization of on-screen options and occasionally inconsistent treatment of the physical controller are still alien and frustrating to me, despite having used some iteration of the command scheme for almost six-years now. No, sir, I don't like it.

Fortunately, beneath the dashboard display is a massive bank of physical buttons with shortcuts for navigation, disc (which can be tapped multiple times to cycle through the many digital media sources), radio, telephony, and more. I'd suggest you use these quick shortcuts for navigating rather than fooling with complicated and many-layers-deep interface of the COMAND system.

The list of audio sources is, thankfully, more complete than most, and the optional Harman Kardon surround sound audio system is equally impressive. Standard sources include a six-disc in-dash DVD changer, Bluetooth hands-free calling and audio streaming, USB connectivity for mass storage devices, an auxiliary input, an SD card slot, and a 30-pin iPod connector. Users of newer iOS devices that use the Lightning cable will need to purchase a lightning to 30-pin adapter -- according to Editor Wayne Cunningham's testing in the contemporary CLA250, simply plugging into the USB port won't work -- which is a black spot on the otherwise solid list of standard audio sources.

Mercedes-Benz Media Interface

A 30-pin adapter in our brand new Benz?! What year is this?

Antuan Goodwin/CNET

Our vehicle was equipped with an optional $3,870 premium package that adds an 80GB hard drive-based navigation system (with 10GB dedicated to music storage), which isn't really worth the money, and the aforementioned Harman Kardon premium audio system, which is definitely worth the bucks. Audio quality is strong and balanced. Bass response isn't as bold as some of the other Harman Kardon systems that I've tested recently, but the entire system benefits from being better-suited for almost any genre of music, rather than targeting the thumpier, boomier characteristics of pop, hip-hop, and electronica. Don't get me wrong, you can still fill the cabin with the wub-wub-wub of dubstep should you want to, but you can also enjoy more delicate passages as well thanks to clear highs and mids.

The premium package's Navigation system features enhanced voice control, which is good because you can enter an address from street number to city in one go (without individual prompts for each chunk), but I found that it required a lot of clarification and confirmation once it had listened to my inputs. Speaking more slowly and deliberately than I normally would made the recognition more accurate, but I've been spoiled by the conversational voice recognition of Siri and Google Now.

harmon kardon a-pillar tweeter

The Harmon Kardon audio system is the brightest element of the E-Class' infotainment tech offerings.

Antuan Goodwin/CNET

I was pleased to see that the COMAND system can receive SMS text-messages from a Bluetooth-connected phone, but was immediately disappointed when I noticed that there's no way that I saw to have received messages read aloud without stopping the vehicle and digging into a menu with the COMAND controller (at which point, you may as well just grab your phone from the cupholder). I also saw no way to respond automatically to incoming messages with an "I'm driving, call you back" message, or with canned responses like "Running late" or "Yes/No." Even a dirt cheap Nissan Versa can at least do that much.

Our vehicle was also equipped with the mbrace2 telematics and Mercedes-Benz Apps, but neither system actually worked once during my testing. Having tested the systems a few times before on other Mercedes-Benz vehicles, I'm not convinced that it would have mattered if they did. The apps aren't well integrated with the rest of the infotainment system, are difficult to use or irrelevant to the driving experience, and are too sluggish to use even when they do make their connection to the Web. Don't even bother with this check box or corner of the COMAND interface.

A very particular parking assistant
The 2014 E250 BlueTec may fall a bit flat where dashboard tech is concerned, but its driver aid and convenience tech offerings are pretty darn good.

For starters, we've equipped the $1,500 Lighting package, which replaces the headlamps with full-LED illumination. The forward lights are steerable with the front wheels to help bend light around corners at night and feature adaptive high beams that automatically dim when the Mercedes-Benz' cameras detect other vehicles ahead.

For $2,800 more, we've added the Driver Assistance package, which adds the automaker's Distronic Plus adaptive cruise control with integrated lane keeping assist. Activating this system will not only maintain a safe driving distance with a leading vehicle (all the way down to a complete stop), but it will also add assistance to the electronic power steering system to help keep the vehicle between the lane markers should your attention drift. Momentarily taking hands from the wheel while testing, I was able to watch the system steering the vehicle autonomously for a few seconds before a warning instructed me that driver input is required. The car won't drive itself yet, but it's getting there.

Also part of the Assistance package is a blind-spot monitoring system, a forward-collision warning system with pedestrian detection, and low speed-collision warning system with rear cross-traffic alerts. When the system detects you're about to back into a pedestrian, or that a car is approaching while you reverse, it can automatically grab the brakes for you while sounding an alert. It's the kind of system that you'd hope never to need to use, but I like that it's there.

The last bits of the driver aid tech come in the form of a $1,290 Parking Assist package. This kit replaces the Premium package's rearview camera with a Surround View camera system that offers a birds'-eye view of the area around the vehicle by stitching together feeds from four cameras. At the touch of a button, the driver can also cycle through detailed views at the front and rear bumpers, either side of the vehicle, as well as a standard rearview camera with a wide angle. In conjunction with the light power steering and the front and rear corner distance sensors, the Benz is very easy to park.

Park Assist icons

This tiny "P" icon and the white arrow to its right are the only indicators that the Park Assist system is working.

Antuan Goodwin/CNET

However, this Parking Assist package also features the automaker's Active Parking Assist and Exit system, which can automatically detect parallel parking spots and then steer the vehicle into the space. When it's time to go, the system can automatically steer the vehicle out of the spot...at least, in theory.

In practice, I spent a week trying to find the hidden controls for the system. It took about a dozen attempts and a few YouTube video tutorials to figure it out. When driving at low speeds, a tiny blue "P" appears within the speedometer and, when a space is detected, a tiny white arrow appears next to it. Next, you'll stop the vehicle, put on your turn signal, and shift the car into reverse, at which point you'll see a prompt asking if you want to use the Parking Assist. Tap a button on the steering wheel and then ease off the brake while the Benz steers itself into position.

That sounds simple in hindsight, but there were a number of issues I ran into. For starters, the little white arrow is easy to miss while driving down the road and watching for opening car doors and pedestrians. You'll also have to drive about half a car's length past the spot before the Benz realizes that it's passed a spot, I prefer to start parking earlier than that. Additionally, that little white arrow is only there for an instant, roll a few feet too far and it's gone until you pass another spot. Also, there's no onscreen prompt until you activate the turn signal and place the vehicle in reverse (and in that order) and nowhere is it explained that this is what's expected. Finally, should you make any input to the steering wheel or brakes before confirming that you want to use the parking assistant system, the prompt disappears until you drive past another space.

Park Assist prompt

Perform the steps in the right order and the Benz may ask you if you'd like to use the Park Assist.

Antuan Goodwin/CNET

Compare this to the Ford parking system's steps: hit the clearly marked park button, drive until you hear a beep, put the car into reverse and let go of the wheel. You will see that by attempting to automate many of the steps and prompts, Mercedes-Benz has unintentionally made the system harder to use consistently. Once you get the steps right, the Benz parking system performed flawlessly, but unless you're an absolutely terrible parallel parker, I'd recommend skipping the parking assistant until Benz works out the kinks with the interface.

In sum
Our $67,039 as-tested price for this 2014 Mercedes-Benz E250 BlueTec includes the $51,400 base price, $925 destination charge, all of the options listed above, and a few more convenience and luxury goodies. There's an additional $650 for a push button starter (which really should be standard), and $450 for cooling ventilation on the front seats. For $660 more, the driver's seat gains active bolsters and massage functionalities. Another $560 gets the laziest Benz owner an electronic trunk closer. There's also $720 for Obsidian Black Metallic paint, $300 for rear spoiler, and $1,620 for Chestnut Brown and Black leather interior with Black Ash wood trim.

You could save a few thousand dollars over our as-tested price by simply picking a different color paint, different interior trim, skipping the automatic parking system, and avoiding the app integration.

E250 BlueTec

The E250 BlueTec offers great efficiency, power, and driver aid tech, but the dashboard tech lags behind the competition.

Antuan Goodwin/CNET

Compared to similarly priced premium diesel sedans from BMW and Audi, the Benz is less powerful, less sporty, but more efficient. I'd wager that it is no less great on the road, in real world driving conditions. The E250 BlueTec's safety tech is also very good, with useful nods toward autonomous driving, even with the wonkiness of the Park Assist's interface. The Mercedes-Benz dashboard and infotainment tech, however, will continue to lag behind its competitors until the automaker rethinks, refreshes, and totally redesigns that dated COMAND system.

Tech specs
Model2014 Mercedes-Benz E-Class sedan
TrimE250 BlueTec Sport
Powertrain2.1-liter twin-turbodiesel, seven-speed automatic transmission, RWD
EPA fuel economy28 city, 45 highway, 34 combined mpg
Observed fuel economy27.0 mpg
NavigationOptional 80GB HDD navigation
Bluetooth phone supportStandard with audio streaming and SMS messaging
Disc playersix-disc in-dash DVD
MP3 player supportanalog 3.5mm auxiliary input, 30-pin iPod connection, USB, Bluetooth audio streaming, SD card slot
Other digital audioSiriusXM satellite radio, 10GB HDD music storage
Audio systemHarman Kardon 5.1 surround
Driver aidsAdaptive cruise control, lane-keep assist, blind-spot monitoring, parking distance sensors, Surround View cameras, Parking Assist automated parallel parking, pedestrian detection, forward-collision warning, brake assist
Base price$51,400
Price as tested$67,039