24 replies to this topic

[focusdriver]

I've had this car for a few days, it's a 55 plate which has done 80,000 miles.

I was expecting good mpg from this but so far I'm getting 37mpg - I do mostly motorway travelling and always set the cruise control to 80mph. I filled the tank this morning and the trip computer showed that I would do 407 miles.

Is this normal for this car? I was expecting 40-45mpg at least!

TIA

[hillmangimp]

Hi,

Just as a comparison I bought a Focus 2.0 TDCI last December with 90k on the clock (2005 55 plate). The car has now done approx 97k. At 70 mph I get 60 mpg. Above this it averages anywhere between 50-55 mpg. The only time I got mpg the same as yours was this summer travelling around West Midlands Safari Park (35-37 mpg with the air con on)! Your MPG does look to be on the low side but it may be due to driving style (harsh accelaration maybe?), but even still I would expect it to be in the 40's at least. If the car is otherwise running well I would not expect low mpg to be due to any technical problems with the car. Does the car run ok? (start well, pick up speed etc)? I have a friend who does have a 2006 1.8 Tdci and he claims that he easily gets between 55-65 mpg.

[InstructorPiggy]

Big jump down in mpg from 60 to 70 and even bigger to 80.

Plus, the limit is 70.

What is the service history like?

Old oil and blocked fuel filter can make quite a big difference.

Plus the fuel itself, I can get an extra 4/5mpg over a whole tank if I get Shell/BP rather than cheaper fuels.

Hope these help,

Piggy

[focusdriver]

Thanks for the advice guys.

I drive pretty conservatively, and don't accelerate hard (I think). The car runs really well, no problems with starting or picking up speed.

I forgot to mention - it has no service history whatsoever - this may be the problem now I think about it . I bought the car on the weekend from a local garage - the salesman did say he'd change the air and fuel filter but I haven't checked if they have - I'm ringing them in the morning.

I suspect an oil change may be due - can you recommend anything else?

I'll do 70 on the way to work tomorrow and see if that makes a major difference in the mpg.

Thanks Again.

[thesilverfox]

Thanks for the advice guys.

I drive pretty conservatively, and don't accelerate hard (I think). The car runs really well, no problems with starting or picking up speed.

I forgot to mention - it has no service history whatsoever - this may be the problem now I think about it . I bought the car on the weekend from a local garage - the salesman did say he'd change the air and fuel filter but I haven't checked if they have - I'm ringing them in the morning.

I suspect an oil change may be due - can you recommend anything else?

I'll do 70 on the way to work tomorrow and see if that makes a major difference in the mpg.

Thanks Again.

Better still, do 60mph. I occasionally do a 60mph run from Liverpool to Luton or Liverpool to Southampton etc. Only when bored of course.

I've returned over 65mpg frequently on those runs, with the car in my sig, also a 1.8TDCi (2007/07)

Sit at 80mph, I get around 45mpg. 70 is more 50-55mpg.

If you change gear above 2k rpm on the way there, it really makes a difference to consumption - try gear changes aroun 1500-1700 revs where possible and you can get some ridiculous efficiency from this engine.

Shame it's absolutely pig slow (I had an ST170 before it though)

[hillmangimp]

If a service is due I'd get it done ASAP as diesels don't like having services delayed/missed. As you say would be ideal to change the fuel, air and oil filter. With regards to oil, as long as the right one is used it should be ok. For the record I used Ford Formula E which is ok in price and the oil that Ford reccomend. Also might be worth checking tyre pressures, if the car has been standing for a while at a dealer, these may have dropped below the specified level.

[mkaminski100]

There is a massive difference between TDDI and TDCI consumption. TDDI can do 65 on the run and I can only get around 37-38 from TDCI. My colleague has the same problem and is also doing 37-39MPG. These engines are just !Removed! thirsty.
I will readjust timing belt in mine and recode injectors.
You can also try disconnecting MAF sensor (connection on pipe going from air filter) and check if there’s any difference. It should have less power, but if there’s no difference, your MAF is knackered.
I have also noticed that the trip computer is showing instant consumption of even 5MPG when the car starts moving. It’s odd, but this computer is more or less useless..

[hillmangimp]

There is a massive difference between TDDI and TDCI consumption. TDDI can do 65 on the run and I can only get around 37-38 from TDCI. My colleague has the same problem and is also doing 37-39MPG. These engines are just !Removed! thirsty.
I will readjust timing belt in mine and recode injectors.
You can also try disconnecting MAF sensor (connection on pipe going from air filter) and check if there’s any difference. It should have less power, but if there’s no difference, your MAF is knackered.
I have also noticed that the trip computer is showing instant consumption of even 5MPG when the car starts moving. It’s odd, but this computer is more or less useless..

Disagree that TDCI is '!Removed! thirsty'. As mentioned in a previous post I can get similar MPG to an older TDDI engine from my 2.0 TDCI engine travelling at the legal limit. Even pushed hard on the motorway I get 50 plus MPG. I also know of people who get better MPG from their Focus than me without having to drive like a nun. However TDCI (and common rail in general) appears to be far more complex technology than previous gen diesel's. As it stands I would much rather have a TDCI compared to TDDI due to the performance and refinement it offers (and happy with MPG as well). If it goes wrong might be a different story though!

[focusdriver]

I spoke to the dealer who sold me the car - he said that he'd changed the oil, and changed the air and oil filter. I haven't checked yet - will make sure that he actually has tonight. Also, I'll check the tyre pressures tonight too.

Will changing the fuel filter make any difference??

I drove in at 70 today all the way - all motorway travel and the trip computer showed 40.2 mpg. The dealer also said that this might be reset as it's been sitting idle on the forecourt for a while.

Tomorrow I may even try 60!!!

Even 40mpg is not what I was expecting. I sold my SAAB 93 Turbo to get a more economical car but that was doing 37mpg.... (the Focus is still half the price on road tax though).

[focusdriver]

FINAL UPDATE:

Seems the salesguy was right - I reset the mpg before I left work. Drove home (about 25) miles and the mpg indicator said 50.5mpg.

Suppose the moral of the story is always reset the mpg before taking a reading. Possibly the car had been test driven a couple of times and probably driven hard to see what the power was like. This must have caused the low mpg reading.

BTW : the garage had changed the oil, oil filter and air filter before I had the car. I'm still to check the tyres but doubt they will be low.

Thanks Guys.

[mkaminski100]

Quick question. Does anyone have a proper trip computer manual? The one in User manual is crap as there ary many extra options, like when pressing right button, average consumption will change and might go down to 5.5 MPG.

[mjt]

That's because the average is just that - the sum of a number of instantaneous readings divided by the number of readings. The instantaneous readings jump around all over the place so the initial average reading reflects what the instantaneous value is at the instant you press the reset.

[mkaminski100]

Yes, I know that, but start pressing big button (is it “R”?) when on idle and find that average consumption will change few times and will go down to 5.5MPG. what’s that for? Saved readings from some time period (like last hour, last 3h, last day?) Manual doesn’t say anything about it.
Vx trip computer is very easy. Reset every full tank and it will give you an accurate average reading, whereas this one showed 46MPG and real consumption was 40MPG.

[thesilverfox]

FINAL UPDATE:

Seems the salesguy was right - I reset the mpg before I left work. Drove home (about 25) miles and the mpg indicator said 50.5mpg.

Suppose the moral of the story is always reset the mpg before taking a reading. Possibly the car had been test driven a couple of times and probably driven hard to see what the power was like. This must have caused the low mpg reading.

BTW : the garage had changed the oil, oil filter and air filter before I had the car. I'm still to check the tyres but doubt they will be low.

Thanks Guys.

Don't use the trip computer for MPG calculations - it's unreliable. Fill to the brim, reset miles. Drive, make a note of miles (after a good 300-400), fill to the brim, make a note of the miles and work out MPG that way.

The on-board computer is a guide, not a definitive.

[thesilverfox]

Yes, I know that, but start pressing big button (is it “R”?) when on idle and find that average consumption will change few times and will go down to 5.5MPG. what’s that for? Saved readings from some time period (like last hour, last 3h, last day?)

On idle, the trip computer should revert to gallons per hour consumption, rather than MPG, as the car recognises it is stood still.