winter is upon us

[vabenzi]

Hi just wanted to find out from fellow mb users about how their cars are performing in the current climate

Just wanted to find out how long it takes on a cold morning for your merc to get up to temperature?

Also have people found that their mpg is reduced?

Reason for the thread was to get basic readings from you guys out there as I've found with my c180k 2008 w204 pre facelift auto.. that the car takes about 15min or more to get upto the optimum temp and I've been experiencing about 18-23mpg (town driving) I'm lucky if I get anything more than that... Am I going wrong somewhere... Tbh the mpg readings reprted I experience all year round but just thought it's a thirsty beast...

Would be good to hear from you guys out there

 

[Deleted member 11979]

E250 cdi cab didn't warm up at all the other day when it was particularly cold, roof down and heater of full along with air scarf gauge didn't hit normal on a 10 mile drive.

I was nice and warm inside though!!!!

 

[Driver15]

Depends where you live... UK is warm at the moment where as Sweden and Norway can be -15 on a daily basis and the cars there are fine.

 

[grober]

The W204 OM 651 4 cylinder diesel has a a variable output water pump to aid the engine reaching optimum operating temperature [ they often go wrong] - dont know about the petrol engine. In general cold petrol engines require mixture enrichment to run properly hence they use more fuel. In some very cold conditions some owners blank off the lower third of their radiator with a bit of card or foil to help warm up times but you must be on the alert for any signs of overheating.

 

[190]

....Just wanted to find out how long it takes on a cold morning for your merc to get up to temperature?

Also have people found that their mpg is reduced?

....I've found with my c180k 2008 w204 pre facelift auto.. that the car takes about 15min or more to get upto the optimum temp and I've been experiencing about 18-23mpg (town driving) I'm lucky if I get anything more than that... Am I going wrong somewhere... Tbh the mpg readings reprted I experience all year round but just thought it's a thirsty beast...

My 2009 C180K should be similar. Is yours the 1.6 Blue efficiency or the earlier 1.8 ?

Mine is a little slower getting up to temp in the winter, it doesn't take 15 mins though, I'd say 5 miles or 10 mins at the most. MPG will fall a couple of MPG when it's very cold but 18-23 MPG doesn't sound right and I would suspect there is something wrong. Perhaps a new thermostat would help. Mine is never used exclusively in town driving so I haven't recorded MPG for a full tank in heavy traffic stop start conditions. In mixed 4 miles commutes and 10 mile commutes I get high 30's and average over the last year with a fair amount of motorway miles is 44 MPG. It's a manual.

 

[GordonTarling]

Don't forget that diesels are now running on winter fuel, so mpg will be a little less, purely because of that. Seems to make about 2 to 3 mpg difference to my E320cdi.

 

[Brian 1]

Winter fuel???

 

[WOODYTHEWISE]

in days gone by, diesel would get wax particles in winter, in winter an additive would be used to prevent this. I think this is what the above posts refer to.

 

[WOODYTHEWISE]

As an aside, my Jag does not have a temperature gauge.

 

[190]

Petrol definitely has a winter blend with lower calorific value due to the inclusion of more volatile fractions.

There is a winter blend of diesel too but I don't know what that the impact on MPG is.

If you look at the whole spectrum of fuel oil the heaver grades have a higher calorific value which is why they run super tankers on the thicker stuff. Any move to a more volatile lighter grade of fuel generally results in less energy content. If winter diesel is lighter then it will probably have a lower caloric value.

 

[flango]

I thought there was no such thing as "Winter Fuel" these days? I can confirm for a fact two of the branded UK fuels run exactly the same spec and additive packages all year round.

 

[vabenzi]

As an aside, my Jag does not have a temperature gauge.

You're pulling my leg right?

 

[vabenzi]

Depends where you live... UK is warm at the moment where as Sweden and Norway can be -15 on a daily basis and the cars there are fine.

Haha true (I'm north west) but I've been monitoring this for some time now and just wanted to find out if it's a common thing

 

[vabenzi]

The W204 OM 651 4 cylinder diesel has a a variable output water pump to aid the engine reaching optimum operating temperature [ they often go wrong] - dont know about the petrol engine. In general cold petrol engines require mixture enrichment to run properly hence they use more fuel. In some very cold conditions some owners blank off the lower third of their radiator with a bit of card or foil to help warm up times but you must be on the alert for any signs of overheating.

Haha might have to give that a try the mpg meter just went down to 17.2 mpg. I just put in 30L of the good stuff like Wednesday last week

 

[vabenzi]

My 2009 C180K should be similar. Is yours the 1.6 Blue efficiency or the earlier 1.8 ? Mine is a little slower getting up to temp in the winter, it doesn't take 15 mins though, I'd say 5 miles or 10 mins at the most. MPG will fall a couple of MPG when it's very cold but 18-23 MPG doesn't sound right and I would suspect there is something wrong. Perhaps a new thermostat would help. Mine is never used exclusively in town driving so I haven't recorded MPG for a full tank in heavy traffic stop start conditions. In mixed 4 miles commutes and 10 mile commutes I get high 30's and average over the last year with a fair amount of motorway miles is 44 MPG. It's a manual.

Mines the 1.8 2008 model unfortunately
Hmm I was thinking about having the thermostat changed but was going to fill up one more time and see if the fuel is playing a part in this.
Man I would kill for those numbers right now this car is taking shots for breakie I tell you. Might have to sort something out either this weekend or the next to get the thermostat changed

Thanks for your input

 

[GordonTarling]

I read on this forum that a different fraction was used for diesel in winter - I can usually tell when it's in use by the drop in mpg. Here's an extract from the original thread -

"United Kingdom
The United Kingdom differentiates diesel fuel into Summer and Winter Fuel according to BS EN 950[31] and BS EN14214 (biodiesel).[32][33] The same numbers are used in the Republic of Ireland. Distribution of winter biodiesel in the United Kingdom starts in November and ends in March.[31]
Designation CFPP value time frame Cloud Point
Summer Fuel -5 °C 16.03. - 15.11. 3 °C
Winter Fuel -15 °C 16.11. - 15.03. -5 °C "

That may have changed in the last couple of years, but judging by my mpg figures, it hasn't.

 

[flango]

You're pulling my leg right?

Hardly any mainstream cars have temp guages these days.

My VW's or Audi doesnt have a dedicated guage but you can access the water and oil temp on the mfd.

 

[190]

The data I'd seen was that the BS spec for petrol specified different vapour pressures at prescribed dates:

Summer (1 June - 31 August)
kPa
45.0 Min
70.0 Max

Intermediate (1 Sept - 15 Oct)
kPa
45.0 Min
100.0 Max

Winter (16 Oct - 15 April)
kPa
70.0 Min
100.0 Max

Intermediate (16 April - 31 May)
kPa
45.0 Min
100. Max

 

[flango]

RVP is manipulated by the refineries based on temperature this is very important in countries with extreme high and low temperatures. I'm not sure how they control this whether it's by blending the different hydrocarbon fractions differently based on temp/season or by controlling the additive package or both.

There is certainly a spec in ASTM standards for min and max RVP based on season. Not sure if this applies to BS as we don't get the temperature extremes will have to look it up. One thing I do know is the cheaper fuels only add cold flow improver from October whereas branded fuels add a an additive package that always contains a cold flow improver component as this component has other properties as well.

 

[uumode]

Hi just wanted to find out from fellow mb users about how their cars are performing in the current climate

Just wanted to find out how long it takes on a cold morning for your merc to get up to temperature?

Also have people found that their mpg is reduced?

Reason for the thread was to get basic readings from you guys out there as I've found with my c180k 2008 w204 pre facelift auto.. that the car takes about 15min or more to get upto the optimum temp and I've been experiencing about 18-23mpg (town driving) I'm lucky if I get anything more than that... Am I going wrong somewhere... Tbh the mpg readings reprted I experience all year round but just thought it's a thirsty beast...

Would be good to hear from you guys out there

I have a W205 2 litre turbo C200 petrol, it's current MPG is pretty disappointing at about 19-24mpg town driving, and not that much better compared to my much older cars from the last decade. Does about 42-44mpg on the motorway on long runs.

Firstly the new W205 has 7 gears for efficiency, it also has a super lean burn engine with direct injection, AND stop start and economy mode which I run. Plus as a new car I've been light footed as the car isn't run in yet. The car is also lighter than my old E Class as it contains more aluminum / panels and is more aerodynamic. But has thick wide tyres.

The old E class has a bigger 2.4 litre engine with 2 extra cylinders to feed (V6) and only has 5 gears, no eco and stop start and is a class size larger and it manages to do about 18-20mpg town driving. Does about 30mpg on the motorway on long runs.

My old Avensis 1.8 litre 4 gear which was quite lean burning VVTi put in about 24-26mpg around town. Does around 42-44mpg on long runs.