Fuel Consumption

[wizzlon]

Just fuelled up today. Normal average is over 55mpg. Got 37 this time. What might be happening...? No real difference in routes/driving. Tyres seem Ok.

[cootuk]

Miscalculation?..does the onboard computer agree?

There will be a drop in mpg due to the colder weather, but usually not so big.

[wizzlon]

Miscalculation?..does the onboard computer agree?

There will be a drop in mpg due to the colder weather, but usually not so big.

Nope- my calcs and fuelly agree. The onboard (which I don't fully understand) has dropped a bit- which over the number of miles on the trip could easily account for lower figure. I'll reset it tomorrow and see what happens.

[johalareewi]

Usual culprits are:

tyre pressure low,

new tyres,

oil overfilled,

it's cold (using engine as a cabin heater),

rain,

it's really cold (using engine to defrost windows in morning),

got more fuel into the tank than usual,

been doing 90 up the M1,

typo in fuelly,

leaking fuel tank.

[dwilson]

Just fuelled up today. Normal average is over 55mpg. Got 37 this time. What might be happening...? No real difference in routes/driving. Tyres seem Ok.

Perhaps you underfilled in the penultimate fill up.

You got 48.9 mpg over 608 miles between 31 October and 10 November. Lower than your average but probably due to the colder weather?

Cheers

[ashpole]

Just fuelled up today. Normal average is over 55mpg. Got 37 this time. What might be happening...? No real difference in routes/driving. Tyres seem Ok.

Is the 226 miles correct? If it was a misread/type and 336, that would give you a more normal 54.8?

[kithmo]

I've seen my mpg on the trip drop this week from around 58 mpg to 45 mpg driving my 3 mile commute. It's colder so I have the heater on, it's damp so I need to demist the screen every morning, it's darker so I have the lights on more and there's more traffic so I have to go with the flow on the short dual carriageway stretch and drive a little faster than I normally did. Not much chance to use EV as the engine cuts in as soon as I put the demisters on. But hey, it's still better than the my previous car a Mondeo 20 TDCi Auto, that did 28 mpg in winter and 30 mpg in summer, although in this weather I do miss the electric front screen and supplementary air heater, an electric element in the heater that gave me warm air within 30 seconds of starting the car.

[wizzlon]

Reset the trip this morning. Have now done 48 miles- mostly town with a bit of A road and dual carriageway. Trip shows 49mpg- which was a struggle to keep. Kept it in eco mode, gentle acceleration and not too much speed. Trouble with this car is it is so economic- and tells you how much- so that when it drops off you get paranoid! I never bothered that much with any of my previous cars.

[timberwolf]

From the front bumper, going back underneath the car, there should be an engine cover, to smooth the air flow and reduce drag. I recall reading someone losing one of those, and it making a big difference in MPG.

[Ancient Nerd]

I've seen my mpg on the trip drop this week from around 58 mpg to 45 mpg driving my 3 mile commute. It's colder so I have the heater on, it's damp so I need to demist the screen every morning, it's darker so I have the lights on more and there's more traffic so I have to go with the flow on the short dual carriageway stretch and drive a little faster than I normally did. Not much chance to use EV as the engine cuts in as soon as I put the demisters on. But hey, it's still better than the my previous car a Mondeo 20 TDCi Auto, that did 28 mpg in winter and 30 mpg in summer, although in this weather I do miss the electric front screen and supplementary air heater, an electric element in the heater that gave me warm air within 30 seconds of starting the car.

I think your problem is the three mile commute. It takes at least that to warm up the car, so the engine is going to be running the whole time. You lose the benefit of the motor taking over at low loads. Also, as the engine is cold, it's going to run at its least efficient.

Just be grateful you're getting 45 mpg. You won't get anywhere that on a conventional car, petrol or diesel, as you found with the Mondeo.

[peak_46]

I've seen my mpg on the trip drop this week from around 58 mpg to 45 mpg driving my 3 mile commute. It's colder so I have the heater on, it's damp so I need to demist the screen every morning, it's darker so I have the lights on more and there's more traffic so I have to go with the flow on the short dual carriageway stretch and drive a little faster than I normally did. Not much chance to use EV as the engine cuts in as soon as I put the demisters on. But hey, it's still better than the my previous car a Mondeo 20 TDCi Auto, that did 28 mpg in winter and 30 mpg in summer, although in this weather I do miss the electric front screen and supplementary air heater, an electric element in the heater that gave me warm air within 30 seconds of starting the car.

I think your problem is the three mile commute. It takes at least that to warm up the car, so the engine is going to be running the whole time. You lose the benefit of the motor taking over at low loads. Also, as the engine is cold, it's going to run at its least efficient.

Just be grateful you're getting 45 mpg. You won't get anywhere that on a conventional car, petrol or diesel, as you found with the Mondeo.

I have now done 2600 miles in the Auris and am averaging 50.1mpg. Most of my miles are on the motorway and that's where car is absolutely useless. Please somebody explain to me the logic of having to make it scream its guts out just to keep up with traffic?? As soon as there is the slightest gradient the rev note goes through the roof unless I want to slipstream an HGV! I'm so glad its not mine but I would love to understand what people see in the hybrid principle as I get nearly the same mpg on the motorway in the wife's petrol Golf.

[kithmo]

Just be grateful you're getting 45 mpg. You won't get anywhere that on a conventional car, petrol or diesel, as you found with the Mondeo.

I am very grateful, using less fuel, no VED and lower insurance makes me a happy chappy, not to mention the lower stress levels due to the Prius being the easiest car to drive.

[Cyker]

My Yaris gets 60+ mpg... :D *ducks*

This sort of thing is why I really don't get why they don't make a diesel hybrid tho'; Diesel engines heat up much faster than petrols and are way more efficient at idle speeds because they don't have a throttle vacuum.

I reckon if they beefed up the electric motor so it was the prime mover and stuck in a tiny 600-1000cc turbo charged diesel as an auxiliary unit, you'd be able to drive to the moon and back on one tank!

[flow]

I've seen my mpg on the trip drop this week from around 58 mpg to 45 mpg driving my 3 mile commute. It's colder so I have the heater on, it's damp so I need to demist the screen every morning, it's darker so I have the lights on more and there's more traffic so I have to go with the flow on the short dual carriageway stretch and drive a little faster than I normally did. Not much chance to use EV as the engine cuts in as soon as I put the demisters on. But hey, it's still better than the my previous car a Mondeo 20 TDCi Auto, that did 28 mpg in winter and 30 mpg in summer, although in this weather I do miss the electric front screen and supplementary air heater, an electric element in the heater that gave me warm air within 30 seconds of starting the car.

I think your problem is the three mile commute. It takes at least that to warm up the car, so the engine is going to be running the whole time. You lose the benefit of the motor taking over at low loads. Also, as the engine is cold, it's going to run at its least efficient.

Just be grateful you're getting 45 mpg. You won't get anywhere that on a conventional car, petrol or diesel, as you found with the Mondeo.

I agree with the short commute - they are a fuel killer.

My morning trip is only about 2-3 miles, with a brief stop inbetween to drop the kids off. My MPG has recently dropped from the high 40's to the middle 40's.

Try pressing ev when you first start up (assuming you have enough Battery left from the night before). This, i beleive, bypasses the initial engine warm up stage.

[FourFourTwo]

I have now done 2600 miles in the Auris and am averaging 50.1mpg. Most of my miles are on the motorway and that's where car is absolutely useless. Please somebody explain to me the logic of having to make it scream its guts out just to keep up with traffic?? As soon as there is the slightest gradient the rev note goes through the roof unless I want to slipstream an HGV! I'm so glad its not mine but I would love to understand what people see in the hybrid principle as I get nearly the same mpg on the motorway in the wife's petrol Golf.

Peak, it sounds like you have got the wrong car for the way you drive and/or the type of driving you need to do.

Hybrids excel at city motoring and bumper to bumper traffic where the electric motor can do its thing, and this is where their fuel figures shine. (That's what people see in the hybrid principle. )

Bombing along motorways, the hybrid technology hardly comes into play and it's not surprising that you may be seeing figures similar to a conventional car.

[Jan&tone]

I have now done 2600 miles in the Auris and am averaging 50.1mpg. Most of my miles are on the motorway and that's where car is absolutely useless. Please somebody explain to me the logic of having to make it scream its guts out just to keep up with traffic?? As soon as there is the slightest gradient the rev note goes through the roof unless I want to slipstream an HGV! I'm so glad its not mine but I would love to understand what people see in the hybrid principle as I get nearly the same mpg on the motorway in the wife's petrol Golf.

Peak, it sounds like you have got the wrong car for the way you drive and/or the type of driving you need to do.

Hybrids excel at city motoring and bumper to bumper traffic where the electric motor can do its thing, and this is where their fuel figures shine. (That's what people see in the hybrid principle. )

Bombing along motorways, the hybrid technology hardly comes into play and it's not surprising that you may be seeing figures similar to a conventional car.

My gen2 averaged 61 mpg, my gen3 is averaging 65mpg.

85 pct of my motoring is on motorways/dual carriageways, 5pct in town and the last is either country lanes or on the isle of wight.

Ergo my gen3 rarely goes near a town (it doesn't like showing up these gas guzzlers )

IMO it doesn't matter where you drive it, the consumption can be obtained it depends entirely on HOW you drive it.

It is quite possible to do 70mph on either the level or very slight downhill on electric with the petrol off!

I've found that using the cruise control does wonders, the computers can drive much more economically than any human

- I'm waiting for the day when I can switch on the cc, add the satnav and sit back, go to sleep and wake up at the destination

[kithmo]

- I'm waiting for the day when I can switch on the cc, add the satnav and sit back, go to sleep and wake up at the destination

You'll be needing the Google Prius then:My link

[johalareewi]

My Yaris gets 60+ mpg... :D *ducks*

Automatic Yaris?

Also, the Yaris is a much smaller car.

Our second car is a 1.3 Yaris (auto) and it averages about 47mpg.

You need to compare the Prius to a similar spec car for meaningful mpg comparisons.

[johalareewi]

- I'm waiting for the day when I can switch on the cc, add the satnav and sit back, go to sleep and wake up at the destination

You just need to book Grumpy Cabbie :D

[peak_46]

I couldn't agree with you more regarding being the wrong car for the job! I'm sure using the car for predominately urban driving it is fantastic. Unfortunately I don't get a choice regarding the vehicle and seeing they bought them on the basis of 60mpg average they are going to be well out of pocket. So far nine of us are averaging 51.6mpg so unfortunately the old chestnut of zero VED is totally blown away by the low fuel economy.

Is there any engineering reason why a CVT box is employed in preference to a standard auto? I'm sure the answer will be weight/size or the technology associated with the blend of power sources but I have to say for me it seems the weak point of the car. The interior is pretty pleasant now I've found a comfortable seating position and the trim doesnt seem too bad. The ride is very good but the inability of the CVT box to transmit the power at a sensible rev/noise level seems to be a let down. I'm sure the Atkinson cycle engine doesnt help but I do worry how much motorway hammer that engine can handle!

[Grumpy Cabbie]

- I'm waiting for the day when I can switch on the cc, add the satnav and sit back, go to sleep and wake up at the destination

You just need to book Grumpy Cabbie :D

Too damn right. You get to your destination in style with the added benefit of having the pleasure of my company AND I have a captive audience to listen to my opinions!

Everyone's a winner

[Jan&tone]

- I'm waiting for the day when I can switch on the cc, add the satnav and sit back, go to sleep and wake up at the destination

You just need to book Grumpy Cabbie :D

Too damn right. You get to your destination in style with the added benefit of having the pleasure of my company AND I have a captive audience to listen to my opinions!

Everyone's a winner

Sorry grumpy, my passport is only valid as far north as Nottingham. Yorkshire won't let me in!

[Jan&tone]

I couldn't agree with you more regarding being the wrong car for the job! I'm sure using the car for predominately urban driving it is fantastic. Unfortunately I don't get a choice regarding the vehicle and seeing they bought them on the basis of 60mpg average they are going to be well out of pocket. So far nine of us are averaging 51.6mpg so unfortunately the old chestnut of zero VED is totally blown away by the low fuel economy.

Is there any engineering reason why a CVT box is employed in preference to a standard auto? I'm sure the answer will be weight/size or the technology associated with the blend of power sources but I have to say for me it seems the weak point of the car. The interior is pretty pleasant now I've found a comfortable seating position and the trim doesnt seem too bad. The ride is very good but the inability of the CVT box to transmit the power at a sensible rev/noise level seems to be a let down. I'm sure the Atkinson cycle engine doesnt help but I do worry how much motorway hammer that engine can handle!

Don't worry! The engine is quite happy at motorway speeds.. It does race away at times, and you ought to hear my Prius on some of the hills in Ventnor!! Look after it, put the right oil in and It will last for years...

[FourFourTwo]

Performed under special, controlled conditions, the Toyota Auris HSD has just entered the Guinness Book of Records for fuel economy with 3.46 l/100km, equivalent to 81.64 mpg.

http://www.automotorblog.com/toyota-auris-hsd-hybrid-enters-guinness-book-of-records/

[Grumpy Cabbie]

I couldn't agree with you more regarding being the wrong car for the job! I'm sure using the car for predominately urban driving it is fantastic. Unfortunately I don't get a choice regarding the vehicle and seeing they bought them on the basis of 60mpg average they are going to be well out of pocket. So far nine of us are averaging 51.6mpg so unfortunately the old chestnut of zero VED is totally blown away by the low fuel economy.

Is there any engineering reason why a CVT box is employed in preference to a standard auto? I'm sure the answer will be weight/size or the technology associated with the blend of power sources but I have to say for me it seems the weak point of the car. The interior is pretty pleasant now I've found a comfortable seating position and the trim doesnt seem too bad. The ride is very good but the inability of the CVT box to transmit the power at a sensible rev/noise level seems to be a let down. I'm sure the Atkinson cycle engine doesnt help but I do worry how much motorway hammer that engine can handle!

The fuel economy will get better as the car beds in - about 3,000 miles and nicely run in about 15,000 miles. You're also in the wrong time of year for the best economy as using the heater knocks a good 5 mpg at least. The cvt box isn't bad, just different. Once you get used to its stepless workings you'll come to love the seamless power delivery, especially when overtaking.

And regarding whether the car can handle the hammer - if my Prius is anything to go by you should be ok. At first I thought the car was too soft but now after 35k miles of taxi hammer it's still running fine and sweet. I truely believe I could get 150k miles with no worries and probably 200k. Obviously the proof is in the pudding and I'll post updates on any findings or problems I may have in the future. This time next year I should be upto 70k miles!