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DaimlerChrysler Introduces the New smart fortwo cdi: 71mpg US, 88 gCO2/km

The new smart fortwo cdi.

DaimlerChrysler has introduced the new version of the smart fortwo cdi: a diesel city car that offers fuel consumption of just 3.3 liters/100km (71 mpg US) with carbon dioxide emissions of 88 g/km.

The new smart fortwo cdi features an enhanced 799cc engine that develops 33 kW (45 bhp) of power with torque of 110 Nm (81 lb ft). That represents a decrease in fuel consumption from the prior model of around 13% with an increase in both power and torque of 10%.

The engine uses a new common-rail direct injection system which builds up high injection pressure of up to 1,600 bar (previously: 1,350 bar) even at low revs, and injects the fuel into the combustion chambers with newly developed six-hole injectors, enabling an even more efficient combustion process.

The new fortwo cdi engine. Click to enlarge.

The three-cylinder engine has also adopted two-phase fuel injection from the CDI engines of its sister brand Mercedes-Benz. A few milliseconds before the main injection a small quantity of diesel is injected into the combustion chambers where it ignites and preheats the cylinders. This results in a noticeably quieter combustion noise level than an engine without this pilot injection. The engine control unit calculates how much fuel is needed and the interval at which pilot injection and main injection take place.

A compact turbocharger is housed in the exhaust manifold. The compressor wheel has a diameter of just 31 millimeters, yet it rotates at up to 290,000 rpm and builds up maximum charge pressure of approximately 1,150 millibars. This charge boost enables the engine to provide 85 Nm—more than three-quarters of the maximum torque—at 1,500 rpm. The smart fortwo cdi accelerates from 0-100 km/h in 19.8 seconds and reaches a top speed of 135 km/h (84 mpg).

As with the earlier models, the engine of the smart fortwo is fitted transversally in space-saving mode in front of the rear axle and inclined at an angle of 45 degrees towards the rear. The consistent use of lightweight materials means that the diesel engine weighs in at just 86 kilograms. The crankcase features a state-of-the-art diecast aluminium bedplate design and the cylinder head and cylinder head cover are likewise made of aluminium.

The three-cylinder diesel engine controls emissions in two stages. The high-tech common-rail injection and the efficient combustion process deliver a low level of engine-out emissions.  Depending on the driving situation and the engine load, up to 60% of the previously cooled exhaust gas is returned to the combustion chambers where it is combusted once again thus greatly reducing nitrogen oxide emissions. The exhaust gas recirculation works with an electropneumatic actuator which enables it to react quickly to changes. An oxidation catalytic converter and an open diesel particle filter are responsible for the aftertreatment of the exhaust gases. These are housed together with the exhaust silencer in a stainless steel case. The smart fortwo cdi is Euro-4 compliant.

The three-cylinder diesel engine works with a newly developed automated manual five-speed transmission which the driver operates by briefly tapping the shift lever on the center console. When briefly pushed forwards the transmission shifts to the next highest gear. Gently pulling the shift lever backwards is sufficient to shift down. Shift paddles on the steering wheel are optionally available and come as standard in the pulse model line. An automatic transmission mode is also available for all equipment variants.

The clutch is opened and closed by an electric motor—there is no clutch pedal in the new smart fortwo cdi. To enable quick intermediate spurts the smart engineers have developed a kick-down function that is activated with the accelerator pedal. This enables the driver to spontaneously change down by one or two gears and to make even better use of the engine’s low-speed torque.

The new smart fortwo cdi also features an extensive range of safety equipment making it, according to DaimlerChrysler, one of the safest cars in its class. The fortwo offers an anti-lock braking system (ABS) with electronic brake-force distribution, electronic stability programme (ESP), brake assist, full-size airbags for driver and passenger, seat belts with belt tensioners and belt-force limiters, safety seats with integral seat belts and the tridion safety cell.

The new smart fortwo cdi is available as a coupé and a cabrio.



And when exactly will the electric version of this car be launched ?


Behold the birth of the ideal PHEV engine. Small, lightweight, efficient, decent power.

Crank up the CR a tiny bit more, add an efficient generator and there we are.

Richard In Fla

Is it coming to the US?


The article doesn't say whether this model will be sold in the US. Anyone know.


The Smart EV has been on trial with corporate customers in the UK since November 2006. See and look under 'models'.


I wish I could find a source, but I believe I was reading on popular sciences website that DaimlerChrysler was supposed to be bringing the smart car to America, so maybe this is it.

What I would really like to see is a Smart forfour, I would be willing to take a bit of a milage hit for the room to put in some of my friends/family.


Wikipedia entry says Daimler chrysler are planning to bring Smart to the US market in 2008. I suspect it depends on whether the CDi version will comply with the slightly different emissions regs, and with the higher Sulphur content of Diesel in the US.



"Slightly" different emissions regs? The NOx emission requirement by itself is 1/6 the level of Europe's. Lev II/T2b5 regs make diesel passenger vehicles emit no more pollutants than a gasoline car.


Zero to 62mph in 19.8 seconds is awfully slow (watch out for that SUV!) I like Clett's idea to use this engine as part of a PHEV genset.


I guess everyone on this blog is for economical cars, but I do not understand why you would make a city car a diesel.
I had this simplistic view of the world: city driving = hybrid, country driving = diesel.
You could combine the two, but the cost goes up further.
Perhaps you could micro-hybrid it.

Also, what will it cost - probably quite a bit considering the level of technology in it.

It is VERY economical, but I just don't get it.


I doubt this tiny car will ever be sold in America since Cerberus now owns controlling interest in Chryler in America.
Too bad BMW did not update original (1959-2000)Austin/Morris Mini which weighed about the same, had a 850cc engine and got 45+mpg, yet had plenty of room for 4 passengers


Now this will appeal to the mini-me in me. But, I will hold
out for the PHEV version with Li-ion batteries and a 60mi
all EV range. These guys got give us emission free capability
for commuting, if they expect us to cram into a shoe box on

Karl Dahlquist

smart has 29000 people on the waiting list in the US...


No kidding. Get with ZAP or Tesla, license the battery and go 100% EV. This is not a car for driving on highways--you'd get squished. Maybe a commuter car. No reason to put a diesel (or gas) engine here. I don't get it either, and one more reason Chrysler is on the chopping block.


with gentle driving you get evene 10% better fuel economy

i know it


If you get any more gentle than 0-60 in 20 seconds, the
thugs here in LA, CA. , will invent a new form of the
drive by shooting, aptly renamed the "pass by shooting".
People don't have the patience to wait behind an econobox
after a stop light. They love to accellerate to the next
stop light to show off their horsepower and braking ability.


We have the smart in Canada. I don't think it's a diesel, it's sold though Mercedes dealers. It costs more than a Yaris, so I don't think people are buying it for economics, maybe to save on pollution, and it's easy to park downtown. Although, it's illegal to park sideways here. Hopefully they'll bring the diesel here. It gets motorcycle like mileage, with a roof.

Lou Grinzo

My wife and I just came back from a few days in Toronto, and we saw about a dozen smart forTwo's zipping about downtown. No matter how many photos you see of them, you can't really understand how tiny these suckers are until one passes you on the street. They are cute though, and at a reasonable price I'd definitely consider the diesel if I were in the market.

We also noticed a LOT of Yaris 5-door wagons, but very few Priuses, for what it's worth.


This car is yet another example of why legislation to promote hybrids is often misplaced. Promoting mpg is what's often relevant, not the technology used to do so. Tell me again why a Ford Escape SUV hybrid deserves a tax credit but this thing doesn't, even though it uses 0.4 gallons of gas for every gallon the Escape Hybrid uses...


In terms of basing policy on results instead of technology I would agree with you Stomv. To that end I would support carbon/pollution taxes as a way of making people pay the full price of their consumption. The only problem I have with diesel is that it is an evolutionary dead end. At least the hybrid gets us closer to EVs.

P.S. some friends of mine own one of these and love it.


The US "08" Smart is a gas engine & has more HP than the last model. They are not bringing in the CDI (at least this first year).

Many are purchasing these as a "statement" car. I have a Scion xA currently & put down my $99 reservation fee for this first US model. I would prefer the diesel as I previously had a VW Golf TDI & loved it.


The only way you will get mein that is with alot of vasoline and a hydrolic ram.


Where I live in the rural midwest we see a lot ot Priuses!...If this lil diesel got the same amount of mileage and was as clean as Prius I imagine I'd see several of them. People here in the midwest do a LOT of driving in between towns/cities...rural is the key word...gas costs almost 4 dollars per gallon...once they get the lithium batteries perfected this cars will be irrelevant...get the 40 mile all electric range for Prius! ~100mpg....oooh I can't wait!!!...its gonna be great...and when MIT perfects the wi-tricity or wireless power transmission...the way Tesla envisioned it 100 yrs ago! Magnetic Resonance power transmission is going to happen people...and when it does no more pure ICE's...just hybrids

We can outlaw ICE's in city and just drive on AC electric drive and only use gas in the rural...


stomv, A vehicle like this would get a credit, just like a hybrid, but it would have to be able to pass the emissions requirements, which euro-4 won't do and the credit is based on how much of an improvement there is vs. the baseline for the weight class, so it might not be a whole lot but it (in theory) could qualify.



Pretty sure that the Smart sold in Canada is a diesel.

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