C350CDI First fuel up... 29.9 mpg

[steve333]

I reset the OBC every fill and record the mileage. I've never had the compulsion to do this with any other car I've owned so I'm not sure why I've started now!

Anyhow, after 7 tank fulls I find the OBC to be consistently 10% to 15% optimistic.

Thats a far bit when you have a big engined petrol car,my obd has showed an average of 22.2 over the last year but doing manual calculations i reckoned on about 20mpg in real life,so your 10%-15% looks about right!

 

[Alscoob]

Out of interest I have the C350 estate & having just completed a 1200mile round trip to Germany, (well loaded on the way out and a few beer crates on the way back) averaged a healthy 37mpg

I was impressed by this considering that for the most, where permitted of course, the speed was between 90 & 120mph on the Autobahn & swift elsewhere, mixed with a few town miles while there.

Best so far has been 41.5mpg on a recent trip to Norfolk on a mix of A & B roads

 

[Red C220]

Out of interest I have the C350 estate & having just completed a 1200mile round trip to Germany, (well loaded on the way out and a few beer crates on the way back) averaged a healthy 37mpg

I was impressed by this considering that for the most, where permitted of course, the speed was between 90 & 120mph on the Autobahn & swift elsewhere, mixed with a few town miles while there.

Best so far has been 41.5mpg on a recent trip to Norfolk on a mix of A & B roads

If that's based on what the trip computer says, take 10% off and it'll be about right.

 

[@MARK]

If that's based on what the trip computer says, take 10% off and it'll be about right.

Also worth asking if you have the C350 CDI with the 231bhp engine or the C350CDI with the 265bhp engine as I would expect the former to be better on fuel.

 

[gIzzE]

Also worth asking if you have the C350 CDI with the 231bhp engine or the C350CDI with the 265bhp engine as I would expect the former to be better on fuel.

That's what I was going to say, but the other way round, the 265bhp version will be much better on fuel as it has the later 7g+ gearbox.

I would expect between 28-38mpg from the earlier one and 35-45mpg from the later model.

 

[Dieselman]

That's what I was going to say, but the other way round, the 265bhp version will be much better on fuel as it has the later 7g+ gearbox.

I would expect between 28-38mpg from the earlier one and 35-45mpg from the later model.

That's why I keep asking about 350Cdi engined cars, I was thinking about buying one and am aware the later 265 Bhp variant is supposed to be more economical, but the economy is so far putting me off still.
It just seems ludicrous that for regular driving modern cars can't match the economy of ones over a decade old with theoretically less efficient engines and aerodynamics.
Add to that the lack of reliability and the cost to fix, it just doesn't make sense to buy one.

 

[Dieselman]

For drivers whose cars are OBDII compliant, it would be interesting to fit a Scangauge to monitor real time economy and also to compare the OBD readout to the accumulated scangauge and brim to brim readings.

Products : Linear Logic - Home of the ScanGauge

 

[fuzzer]

Im sure if you were worried about MPG a C200 CDI would have been a far better choice.

Enjoy the power , enjoy the engine. 30 is still fairly decent overall.

 

[gIzzE]

I just managed 39mpg from my 3 litre V6 W211 E320cdi over a whole tank.
It is one of the rare V6's without a DPF, think there could have only been a few weeks between them adding the V6 and then adding the DPF?

OBC said 40.9, but it works out at around 39.5 doing calcs.

I think that is pretty good for such a big heavy car with 270bhp, Brabus D6 III box on it, and my best whole tankful apart from going to the Netherlands and back in it.

However, if I was to drop £40,000 on a new one I would want to see that every tankful, better gearbox, better aerodynmics, stop start tech etc. etc.


One thing worth mentioning is the fact it had Michelin Alpin tyres fitted for this tank, I know they have a very good rolling resistance figure, but I think more than that is the fact they are softer, quieter and a lot more comfy, which may have made me pootle around more?

But interesting to hear the variations from owners regarding 350cdi as I keep looking at them and really want to bite the bullet.


I would like to hear what tyres and wheel size those who get low 30s are on compared with those who are getting high 40's.

 

[John]

It just seems ludicrous that for regular driving modern cars can't match the economy of ones over a decade old with theoretically less efficient engines and aerodynamics.
Add to that the lack of reliability and the cost to fix, it just doesn't make sense to buy one.

Cars 10 years ago were a fair bit lighter though...

If you look at the weight range from lowest to heaviest diesel in the W210 from around 10 years ago, the range is 1440kg - 1660kg

The current range similarly is 1650kg - 1845kg

More safety and more gadgets, but with a focus on cost I imagine has a bit to do with the ever-expanding wasteline of the E.

 

[Dieselman]

Cars 10 years ago were a fair bit lighter though...

If you look at the weight range from lowest to heaviest diesel in the W210 from around 10 years ago, the range is 1440kg - 1660kg

The current range similarly is 1650kg - 1845kg

More safety and more gadgets, but with a focus on cost I imagine has a bit to do with the ever-expanding wasteline of the E.

Say, 10% lighter, but with engines that are supposed to be 20% less efficient and under-geared axles and worse aerodynamics.

Mass has no bearing on power consumption at constant speed (cruising), only when accelerating.
Is the interior of a W212 any larger than a W210? I doubt it as the w211 is smaller inside.

Heavy cars are due to sloppy design, it's far harder to design a lightweight car.

 

[ndps]

Im sure if you were worried about MPG a C200 CDI would have been a far better choice.

Enjoy the power , enjoy the engine. 30 is still fairly decent overall.

Absolutely, I did consider getting a C250CDI after enjoying test driving one however I then thought that I would always be wishing I had gone for the bigger engine for the fun factor. The lease cost was no more expensive for the 350 too. Fully expected to be taking the hit on fuel economy.

Just returned from a shopping trip into Glasgow, was a 70 mile round trip from Livingston mainly on the M8. OBC reporting an average of 43.5 mpg, so even if it is optimistic by 10%, ~40 mpg isnt bad considering I wasnt really trying to be economical.

 

[st4]

That MPG is fine given the average speed and more in line with what I would expect.

I've been out in a hoon today, and with a mere 221bhp you can have A LOT of fun and go very fast.

 

[st4]

That's why I keep asking about 350Cdi engined cars, I was thinking about buying one and am aware the later 265 Bhp variant is supposed to be more economical, but the economy is so far putting me off still.

Why? You're better of keeping yours until its dead, you're now in the rare position of having very cheap, but good quality motoring.

Unless that is you want the 265bhp car.

Add to that the lack of reliability and the cost to fix, it just doesn't make sense to buy one.

At some stage your wanting of a new car will force you into one, regardless of "sense".

Remember the newer car does have 90bhp and maybe 150ft/lb more torque. Something HAS to give. You will use that extra power for acceleration, its very good fun.

If you don't, you will get a good return on the MPG, like all cars. Its how you drive them. Given you see more than your average 210 300TD driver, there is no reason why you won't roughly average more than your average 212 350cdi driver.

Gizze just posted how he returned 40mpg and was happy with that, on a long haul I see 45mpg +. I am probably more sedate than him. I met with Tim Kemp not that long ago, he reports laughably low MPGs, following him I realised why, for the 1st time in how every many years I really had to press on to keep up with him. He uses the full performance of his car most of the time, I don't, I use less fuel than Tim.

I really don't know what you are worrying about as its not in terms of fuel cost going to be any different to the car you drive, its going to be faster and better equipped and will drive very nicely. ( The only potential worry is the potential long term reliability issues but as hateful as 7g is, its not a massive failure rate and the V6 engine will take the miles you'll throw at it and there are ways to get round DPFs), the E350cdi will be fine on fuel. And they do a 250cdi that's still faster than your car, that's also better on fuel again.

BTW interior space in the 212 is on par with your car, not the more cramped 211.

 

[Dieselman]

At some stage your wanting of a new car will force you into one, regardless of "sense".


I really don't know what you are worrying about as its not in terms of fuel cost going to be any different to the car you drive,

I'm not worrying, just disappointed that economy won't be as good as/better than what I already have, combined with almost certainly worse reliability it seems hard to justify spending a heap of cash...which coming from yorkshire takes some getting round...

 

[st4]

I'm not worrying, just disappointed that economy won't be as good as/better than what I already have, combined with almost certainly worse reliability it seems hard to justify spending a heap of cash...which coming from yorkshire takes some getting round...

So don't buy a new until you have to.

Remember, in real terms the newer Mercedes cost less than your car. Your car was pushing £40k in 1997/8. The current cars cost approx the same and you get more kit.

Naturally, something has to give and its major components are more cheaply made.

If I were you and you had the choice between a new 212 or a used 221 you should look at the S class, you'd love it and given you are almost technically a giant, you'd have a lot more room and a nicer riding car.

Or go left field, buy a used Citreon C6 (IIRC you've ran new ones back in the 90's and you've got two to smoke around in), good engines those PSA/Jag land rover ones and a car that will probably satisfy you more than the Mercedes 212 and rust a whole lot less....

 

[John]

Mass has no bearing on power consumption at constant speed (cruising), only when accelerating.
Is the interior of a W212 any larger than a W210? I doubt it as the w211 is smaller inside.

Heavy cars are due to sloppy design, it's far harder to design a lightweight car.

Yes, so a lot depends on how you use your car but certainly my daily drive involves a lot of acceleration and I would guess most others also given the time of day most commute... unless you live in the middle of nowhere.

Sloppy design is allied to lighter materials not being used - all saves them and costs us money.

Something HAS to give. Probably everyone but you will use that extra power for acceleration, its very good fun.

Just corrected that for you.

 

[Alscoob]

Also worth asking if you have the C350 CDI with the 231bhp engine or the C350CDI with the 265bhp engine as I would expect the former to be better on fuel.

I have the 231bhp with the 7 speed box, but understand that the 265 is more economical, not sure how though

 

[@MARK]

I have the 231bhp with the 7 speed box, but understand that the 265 is more economical, not sure how though

As Dieselman said, it's about advances in efficiency.

So the latest C Class has aluminium wings and an aluminium bonnet etc to reduce weight which should help and the new gearbox is supposed to be more efficient but if you actually use that extra power then I would still expect it to use more fuel as well.

The new C might be more efficient but there are no real major technological advances in there. Just tweaks

 

[steve333]

As Dieselman said, it's about advances in efficiency.

So the latest C Class has aluminium wings and an aluminium bonnet etc to reduce weight which should help and the new gearbox is supposed to be more efficient but if you actually use that extra power then I would still expect it to use more fuel as well.

The new C might be more efficient but there are no real major technological advances in there. Just tweaks

So in 7 years time the c-classes will have rust free wings & bonnets but the rest of the bodywork..............?