fuel economy - 2007 A180 CDI fuel economy

[khkc]

Hello, having read through posts from many W169 owners, it appears that my car could be faulty.

I live in central London, I regularly average 30mpg driving around in the city. Even on the motorways, the car only manages 45mpg when crusing at 70mph.

Mine is a W169 180cdi with the autotronic gearbox. It also has the sports pack hence the 215/45/17 tyres, but the economy shouldn't be that bad, should it? The figures are basically the same as an E220CDI - a much much larger car!

Any advice/suggestion from fellow owners especially those with the sports pack, too?

 

[jberks]

impossible to say as there are so many factors. Road conditions and the like. I can't get 50mpg from my E270 howver I drive it, though the book infers I should be able to. My Freelander is supposed to do 30mpg round town yet the trip computer sits stubbornly around 22mpg. (It starts to creep up when I drive it so I suspect the wife's right foot on this one ;-)) .
Some people claim crazy mpg figures but I'm always suspcious. Whether they only report the downhill journeys or they only drive on empty roads I don't know but cars do vary anyway. I have a friend who claims 60mpg for his mondeo, but he thinks that his is exceptional. I suspect it probably runs a bit lean.

Things you can do are, attempt to coast wherever possible, so anticipate more. Maks sure you haven't got 1/2 a ton of stuff lying around in the boot. Baiscally, rolling resistance and weight are all mpg killers.

On the subject of rolling resistance, tyres are a major contributor. Far more than you'd think. Check your tyre pressures but even the brand makes a big difference. Michelin are allegedly the most economical (though you'll never recoup the extra cost of the tyres in fuel savings but hey). A friend has just changed from bald continentals to new khumos. Whilst he's very happy with the grip/noise and price, he has commented that his mpg has fallen by 7-10%. I have 245 federals on mine and and I suspect that accounts for the fact that I can't reach the claimed figures. Certainly in wet conditions 40mpg becomes virtualy unachievable. I don't know what the standard tyres are on your car but wider tyres=poorer fuel economy so if you have a 'sports pack' then no you'll never achieve the claimed best mpg.

Finally, check things like the air filter. It may be within spec but members have found improvements by changing them anyway.

There was a feature on 5th gear last night. They'd tested a VW bluemotion with a claimed 70mpg. They used it for a few weeks and returned .... 47mpg so you're not alone. Claimed mpg figurea are something to strive for and do give a guide but they are normally a bit optomistic in the real world.

 

[stumpy]

A point to add - it takes many miles for an engine to loosen up fully and give its best performance and economy, diesels especially. My friend has a Range Rover Sport V8d which is improving all the time and he has 30k miles on the clock now

 

[A210AMG]

Hello


We are always supprised with my wifes A class, Its a petrol A210 LWB (manual) and that on varied runs (stop start, and motorway) does over 40mpg regulary and even as high as 47mph. I think her tyres are the same width (I know they are 17")

Think the engine is very lazy as it seems to pull in almost any gear.

Hers is on 30K miles and as mentioned is a manual, but I would hope for more than 30mpg out od a 180cdi ?


Check your tyre preasure for one I think...

 

[NewMB]

My wifes A180 Cdi (2007) has a higher fuelconsumption than my tuned C320 Cdi!

However, as the miles are clocking up, we have noticed an increase in mpg. At 5000 miles we are now seeing approx 36 mpg in town and just over 42 on a long run. Not driving with an egg under the foot.

 

[khkc]

Thanks for the replies so far.

My car has only done 7000 miles, seems like I am getting similar figures to NewMB's A-class.

Whilst I am not expecting it to match the published figures, I would at least expect the car to do more than 45MPG at 70miles an hour on the motorways. From what I've read so far, Hawk20's W169s are getting a lot more mpg that mine even though we probably have similar mileage on the engine.

I do check my tyre pressure regularly, in fact, as a former Honda Insight owner (i drive very economically and used to get 90mpg on the motorways!!), I also over-inflate the tyres to the upper recommended PSI to aid economy, that's why I am somewhat dissappointed by my A Class.

It has been back to the dealer, but they said everything's fine. It is an amazing little car, I just hope the econoomy will improve over time.

 

[hawk20]

First: loads of people have noticed better economy in summer than in winter. In winter the air is colder and denser. The heater uses loads of energy which can only come from fuel. Cold engines take longer to warm up in winter and use more fuel. Turning off the aircon may help. Lots of debate on this as on modern cars the compressors are still going -say some experts on other threads.
Second: on the CVT box driving in C rather than S mode gives a real and definite and significant gain in economy (which did not happen on the S class diesel I had or the E270 or the ML270cdi.) Expect 3-4 mpg better.
Third: the computer read out in the instrument binnacle can be wrong and can be reset. Do a tankful to tankful test.
Both my A's are CVT autos and both are 180cdi's. On a run at 70 (and that means indicated 72/3 according to my Garmin GPS) we can get 50mpg if we avoid hard acceleration (that has a big effect). If we drive nearer an indicated 80 and use more acceleration we see this drop to 45 mpg.

Choice of cruising speed has a significant effect as the AA have noted on all cars.

The claimed combined figure for the auto 180 is about 52 mpg. I aim to get 85% of that on average (around 45). I have found this rule of thumb works on many diesel cars. But it depends how much round town you do and how bad the traffic is.

My brother has a manual A 160cdi and gets over 60 on a run driven gently but he did not get this sort of economy till the engine had done 15,000 miles. Remember diesels often do 300,000 miles so we have hardly started to run them in really. Hope this helps.