C200 cdi 2004 mpg

[RUSSC200EVO]

New to the forum, just a quick question guys I have purchased a C200 CDI 2004, the car is just like new only done 42k in seven years with full service history. Just Driven some 460 miles however very disssapointed with MPG 40 max. Was not driven hard at all. I thought it should do much more. Strange for a diesel the exhaust is very clean not black as per most diesel cars.
Any info would be helpful

 

[jaymanek]

get the Mass air flow meter checked out at a good indie or dealer.

 

[RUSSC200EVO]

Thanks will look for a local indie, nice sec by the way had a 560 sec for many years a while back was sad to see it go

 

[artyman]

That's what I get from my 2008 C200 cdi as well, so you are not alone in being a bit dissappointed. I could exceed the combined figure if my previous car without any problem, with the Merc I can't even get close, never mind better it.

 

[Stratman]

I have the same car (C200 CDI '04) and the long term average is 49.4

On a long run I would be both surprised and disappointed to get less than 55.

 

[RUSSC200EVO]

Quick run up the A30 at 60 driving as gentle as poss this am only doing 43 !!!!!!!!!! Have to get it checked

 

[RUSSC200EVO]

Well guys drove like an old lady this afternoon on A30 only got 43mpg need to get it looked at love the car big time but so dissapointed in mpg :-(

 

[Stratman]

What temperature does the engine run at? Thermostats are known to fail on these engines, affecting efficiency.

 

[cataloyking]

i have a 2010 c200cdi and local driving i get around 31/35mpg on a longer trip the max i have got is 49.8mpg and that is checking tank to tank my previos car a 2007 c200cdi gave me well into the fifties and did not have a dpf a lot of owners are saying the filter is costing them 10mpg anyone else have any ideas

 

[Stratman]

In no particular order, things which could affect consumption are; clogged air filter, faulty Mass AirFlow sensor (MAF), faulty thermostat, split/dislodged turbo boost pipe, leaking fuel pipes, binding brakes and heavy right foot.

 

[Puggy]

this would seem a much discussed subject. My 2004 C220 struggles 30mpg commuting (50% urban) and 40mpg on the most carefully driven A roads. After following many a discussion thread on this subject I decided to put the fuel in and enjoy the car.

 

[diesel demon]

There is a lot of talk that the supermarket fuels return less MPG than the leading brands. What type of fuel are you using. It would be interesting to hear if anyone has carried out a comparison. My C220 CDI seems to be thirsty one day and then more or less on the waggon the next, even though the driving is the same.

 

[Robert-Black]

I have just recently purchased a C220 CDI and first impressions are it is much thirstier than i would've hoped for, just over 40 on a the M/A road run home & mid low 30's since. The car has full MB service & is only on 65k, it runs at 90 degrees so that seems fine, i will have to check all the obvious air filter MAF and such, but i fear it is due to the DPF, so i may well be looking for a company to delete it and reprogram my ecu in the not too distant future.
Anyone here had this done or know of any companies that offer this service?

PS Other than this it is a lovely car.

 

[recardo]

looks like there are a few of us in the same boat - low 30s in town 40ish on the motorway. I'm getting between 36 and 38mpg tank to tank.
these are my imporved figures since changing the thermostat, also changed 2 injectors and the turbo. MAF is the only bit left for me to change but been holding back due to the cost/lack of guarentee it will increase mpg. car drives great so no indication that the maf or anything else is wrong.

would be interesting to see if anyone else experiencing dissapointing fuel consumption benefits from a changing the maf?

 

[Robert-Black]

I thought MAF's were cleanable, a MAF is a housed piece of wire with some support circuitry, when i owned an Audi, we used to clean the wire with a soaking in lemon juice or isopropol (ipa solvent), is the Mercedes MAF any different?

 

[diesel demon]

With my car it depends massively on how I drive. This morning on the run from Near Royston to East London (Near Docklands) I averaged 53.2 MPG. That was a door to door mileage including the start up and 30 mile an hour speed zones until I got onto the A roads. Total distance of 43 miles at an average of around 38 mph. I didnt go over 60 MPH which wasn't difficult due to the speed of the traffic flow anyway. I find that as soon as I incease the speed to 70 MPH on a urban cycle, the MPG takes a nose dive to low 40's and any incline reduces the MPG quite dramatically. When in top gear, driving at 56 mph isnt really economical as the car is out of its torque range so try 60 to 65 MPH for best MPG. It also gives you Inertia to climb the inclines.

 

[RUSSC200EVO]

I have decided to book into a indie dealer in Plymouth when i get the time, strage but the exhaust is very clean no black diesel soot, looks like new ????????
Having covered some 900 miles since purchase the exhaust is still gleaming inside.
it is the original exhaust.

will keep you up to date, big thanks for the help guys

 

[RUSSC200EVO]

Guys

Just done a quick calculation re fuel put in tank and miles covered average 37mpg.

 

[recardo]

Guys

Just done a quick calculation re fuel put in tank and miles covered average 37mpg.

similar to mine then.

with regards to exhaust you could have a DPF. mine has, and these can contribute to a lesser avg mpg than non-DPF cars.

 

[Tinkerer]

CDI engines are at their most efficient when at their operating temperature i.e. 90C if you are up to temp on the motorway remember to check the temp again when you go into slower sections of you journey, if it cools down it will be less efficient. Once it gets up to temp it should stay there if it cools down look to the thermostat. I get between 45 - 52 mpg from my 2001 e220CDI regardless of what grade of fuel I buy ..... personally I think that diesel is diesel , trading standards control the spec ..........