Technical Terrible MPG from the 120bhp?

[RichDoblo120]

Just completed a 2000 mile round trip to the Med and my average mpg (according to the computer) was 31mpg.
I must admit there were 4 adults and 3 kids and a shed load of luggage in the car, and we were cruising at 130kmh most of the time but still, I had hoped for a little better than that.
I'm sure the mpg was better when it was new.

Maybe that figure is pretty good considering the weight the poor old Doblo had to carry?

What do you reckon?

 

[chrisb100]

Rich Thats bad

i have just done 1500 miles over past 3 weeks around britain, mix 70% M and A roads the rest round town in my 105bhp 06 cargo van fully loaded van as well as 2 adults and toddler. i don't drive it soft and have been very pleased with an average 47.1 mpg ( computer)

I always use millers sport4 and have found through trial and error that sainsburys diesel suits my van best both in mpg and pick up etc.

31mpg I couldn't get that if I drove to london flat out in first gear.

a check up is probably needed

 

[RichDoblo120]

Rich Thats bad

i have just done 1500 miles over past 3 weeks around britain, mix 70% M and A roads the rest round town in my 105bhp 06 cargo van fully loaded van as well as 2 adults and toddler. i don't drive it soft and have been very pleased with an average 47.1 mpg ( computer)

I always use millers sport4 and have found through trial and error that sainsburys diesel suits my van best both in mpg and pick up etc.

31mpg I couldn't get that if I drove to london flat out in first gear.

a check up is probably needed

I'm sure it's the 120 engine. Other 120 owners have reported poor mpg too.
I think the van has the 105 engine which seems to be the best all round.

A warning to other potential Doblo owners...if you want a 5 seater, buy the 105. If you need a 7 seater buy the 1.3 litre.

 

[chrisb100]

seems to be the case regards the 120bhp engine but why!!!

Its the same engine but with different a Variable geometry turbo DPF and altered ECU.

So why such a difference???

 

[RichDoblo120]

seems to be the case regards the 120bhp engine but why!!!

Its the same engine but with different a Variable geometry turbo DPF and altered ECU.

So why such a difference???

I don't know.

As far as I can tell, the Grande Punto has the same engine too but that produces 130 bhp, and one of the Alfas also has this engine and they squeeze 150 bhp out of it.
I wonder what the mpg is like on those?

 

[Broadpete]

HI Rich - Its the same story as before I fear. The modern 120hp with all its 'green' kit uses far for fuel than the earlier engines (thereby rather defeating the objective!). The problem can be minimised up to about 65mph but then consumption falls off a cliff.....and just think; if you'd driven everywhere at 65mph you might still be on holiday!

Peter

 

[sludgeguts]

130kph? that's a shade over 80mph, hardly suprising the fuel economy was so bad.
Although large diesel engines are economical, they seem to have a small window of 'best economy' when it comes to cruising. There is also a point at which rolling drag and wind resistance seem to require more fuel to overcome.
I used to own a pug pickup with a 2.3 diesel engine. Best economy was achieved at a constant 56mph no matter how much I was carrying.
With regards the dobbin, I find best economy is achieved around 60mph.
I've not yet done a long journey to prove this speed but I'm doing a lot of short journeys (20 miles each way) along dual carriageway which is showing a considerable increase in economy (based on miles travelled / fuel guage reading as opposed to computer).

I'm not entirely convinced about the 'problems' of the 120bhp engine - it may simply be down to the way it is driven.
No disrespect intended, I have no idea how you drive but I see and hear how vehicles are driven around here.
You cannot push a 120 from a standing start like you push a 105 & expect same economy.
Even just revving the engine at the lights/junction will use more fuel in the 120.

Believe me, I know it is really frustrating to pootle along at 56/60mph whilst the old crates are sailing past but I'd far rather enjoy the ride than sit & watch the fuel tank empty. I'ts nicer to get there and back on a tank than 1.5 / 2 tanks of fuel - especially at today's prices.

One other thought. If you have a car loaded with 7 plus luggage, you will use more fuel pushing the car up to speed than many miles of motorway driving. It may be that all the starts you were doing returned 10mpg whereas the motorways returned 45 - 50mpg so the computer is showing a low average?

 

[RichDoblo120]

130kph? that's a shade over 80mph, hardly suprising the fuel economy was so bad.

that's the speed limit in France and if you do much less than that you start to feel like a hazard to other drivers as they're all doing at least that speed.

Although large diesel engines are economical, they seem to have a small window of 'best economy' when it comes to cruising. There is also a point at which rolling drag and wind resistance seem to require more fuel to overcome.

The huge roof box I have might not be the best when it comes to wind resistance

I used to own a pug pickup with a 2.3 diesel engine. Best economy was achieved at a constant 56mph no matter how much I was carrying.

I had a 505 with the same engine and it would never average more than 35mpg. It must be the way I drive

I'm not entirely convinced about the 'problems' of the 120bhp engine - it may simply be down to the way it is driven.
No disrespect intended, I have no idea how you drive but I see and hear how vehicles are driven around here.
You cannot push a 120 from a standing start like you push a 105 & expect same economy.

I must admit that I don't drive it too carefully. I like to keep the revs between 2 and 3 thou because there's not much power below that, plus I drive the 'old fashioned' way, braking as little as possible and using the engine brake. That's how I was taught, but it might not help with fuel economy.

 

[RichDoblo120]

To be honest I'm thinking about trading it in if I can't get the mpg down by a long way.
I've already spotted a cheap 7 seater that should be better on fuel, a 1.5 Diesel Dacia Logan

 

[Ulpian]

Seven people and a roof rack, doing 80, is going to wreck consumption. I usually get around 45-55 in my '93 100bhp JTD at 70- 80mph, but alone and with only a couple of bags. Two up, with a full boot and a varied mileage including lots of short journeys, at night, I get 40-45. I'm off on a long trip soon and I'll monitor the consumption to see what I get.

 

[chrisb100]

other thing to think about hear is that even with all the gear, 4 adults and 3 kids and a streamlined roofbox at 80mph 31mpg shouldn't be happening.

as some of you may know I have a digital tuningbox fitted boosting power to over 135bhp through injecting more fuel in the cylinders at each burn.

having this DIGITAL ( there is a difference)box set to MAX power I still to this day driving like a crazy man could never get it below 40mpg, if anything it has increased mpg by 3/4.

It could be that in RICH's case as each engine is slightly different I would like to think that it could be a fault, by the sounds of it a heavy foot and 80mph is no sin if it is i'm dammed:devil:

No No to the Dacia

 

[RichDoblo120]

I know it's not much but I just did a little 10 mile round trip and re-set the trip meter. I drove as gently as I could, not letting the revs go above 2k and when I got back it said 'average 41mpg' .

If that's the best I can hope to get, driving like a 90 year old lady on valium, then I may as well give up and drive in my usual way.

Where can I buy a Dacia?

 

[Ulpian]

What do other 120 owners get I wonder?

 

[T14086]

has it got a DPF?

 

[dobloseven]

I went from 03 and 05 jtds which both did 38 mpg in stop start town driving although the readout said much more to a 120 multijet which does 33 with the readout saying the same.Using the aircon reduces these figures by about 10 percent fast motorway driving makes little improvement A road driving improves them by about 10 percent again. 120 seems to perform better at high speed and when laden pulling strongly when the 100 and 105 would have run out of steam.

 

[RichDoblo120]

has it got a DPF?

Yes, I'm sure is has a DPF.
I get a little injector symbol light up when the ignition is switched on, is this something to do with the DPF?

By the way, it's just had its second service and it's only done 13k miles.

I went from 03 and 05 jtds which both did 38 mpg in stop start town driving although the readout said much more to a 120 multijet which does 33 with the readout saying the same.Using the aircon reduces these figures by about 10 percent fast motorway driving makes little improvement A road driving improves them by about 10 percent again. 120 seems to perform better at high speed and when laden pulling strongly when the 100 and 105 would have run out of steam.

Sounds like all the 120's are the same.
It does pull really well with a heavy load. We cruised down to the Med at 80 nearly all the way with all that load on board and if I needed to I could still accelerate if I wanted to make a quick overtake.
I suppose poor mpg is the price you pay for more power.

 

[deeyup]

I don't know.

As far as I can tell, the Grande Punto has the same engine too but that produces 130 bhp, and one of the Alfas also has this engine and they squeeze 150 bhp out of it.
I wonder what the mpg is like on those?

I had the GP Sporting 1.9, 130hp, I used to average around 45mpg.
This was the same kind of driving that saw 55mpg in a golf gttdi 110, and 60mpg in a clio 1.5dci 80.

So not the best for economy this engine in 130hp tune.

Deeyup

 

[T14086]

There is a update for vehicles with DPF (think yours has had it though) ...anyway Rich considering the weight in that doblo at that speed it aint that bad.

 

[Ulpian]

Fiat Diesels are sweet and smooth, but not as economical as other makes. All the comparisons, both tests and anecdotes, seem to confirm this. Petrol cars need new exhausts and catalysts from time to time as well, so I'm not certain holding DPFs against Diesel cars is necessarily fair. I've just had a new center (exhaust) section fitted to my Doblo - it finally snapped just behind the catalyst/DPF?,and the cost fitted was £225. A lot, but a lot less than Fiat quoted. The car seems to be running very well...fingers crossed etc. etc....

Cars are always going to be expensive, but what's the alternative unless you don't need one for work?

 

[Broadpete]

There is a update for vehicles with DPF.

Hi T14086, can you tell us anymore about the update, so we can see if it may help the rest of us? Do you know when it was issued, and perhaps from which date 'new' cars would have been supplied with it already installed? Many thanks.