What Mpg Are You Really Getting?

[fromspain]

1,0 vvt-i

5500 kms (about 3400 miles)

Average: 40 mpg

My best: 49.61 mpg in motorway and country road

Most of driving in urban traffic with jams

[shuffly]

greetings,

So the aygo has started as a driving chool car,

MPG first fill 48

then drops to 45 on second fill,

its leveled off at about 45-46 which isnt too bad with two people, the cone and sometimes aircon on.

the best car was my diesel yaris which did 55-58 under same conditions.

Ian

[ewans]

First tank full from new gave 48mpg all urabn city driving mostly short trips of around 5 miles.

fairly happy with that and it should improve with time ;)

[aygoal]

First tank about 53MPG, but difficult to tell as one extra 'click' can make 1 litre difference which is a difference of 2MPG.

That MPG is not bad though especially as I was playing a bit as well - the engine note at high revs is addictive!!! ;)

[shuffly]

gone down to 49.5 on last few tanks

[ewans]

2nd tank from new gave 59mpg! 2 A road long trips and the rest in and around town, happy with that :D

[hora]

I drive 'enthusiastically' but smooth. From full tank to the start of the 'beep' its 350miles so 45mpg.

however from the beep/low fuel warning I'm not sure how much more is in the tank?

[aygoal]

Done 2000 miles now about 52 to the gallon

[Gryzor]

Is there a problem with my Aygo?

That's about 39mpg (imperial) as far as I can see... And I drive rather economically. That's both in-city and on national roads...

[hora]

Are you sure you dont rev hard in 1st, 2nd, 3rd? Or do you use the same petrol station (rough fuel?)

[adilmon]

Is there a problem with my Aygo?

That's about 39mpg (imperial) as far as I can see... And I drive rather economically. That's both in-city and on national roads...

It's common to think that keeping the revs low is the most eco. When the revs are low, overloading the engine (sometimes called over-torquing) reduces the fuel economy. I’ve been playing with my scangauge II, which displays live information regarding the percentage load on the engine at the current rpm

[Gryzor]

Thanks for your reply.

I usually stay in the middle - up to 30km/h tops for 1st gear, 55km/h for the second, that would take me up to 3.5krpm at most I think. Always the same fuel - BP Ultimate 100.

My first service is nearing (around 12k km?), so maybe I'll tell them to check it out - but am I correct to assume these are NOT normal figures? I think a colleague's Turan burns about as much (7.5l/100)!!

[Jazzy Jase]

I normally average about 46mpg, but with high petrol prices at the moment I've been driving a bit more economically.

I got 49.7mpg on my last tank and I'm determined to beat 50mpg on this next one. So far I've done 132 miles and the fuel indicator still has all the bars filled!

[Leeky]

Reading through this thread i cant believe people are only getting as little as 35mpg sometimes

I dont think i could get that bad economy if i tried.....(1st gear down the M4 bouncing off the rev limiter?)

I average 65mpg commuting up and down the M4 between Reading and Slough and on good days (when the m4 doesnt become a car park) i've managed to hit the brochure's stated 70mpg+

I think the most important thing is to come away from the lights smoothly and to not rev the engine more than is needed to get you where you are going.

I drive in a totally different style in the Aygo to what i do in the Supra (for obvious reasons). I try to pull away gently from stationary and use the gearing as best i can. I change up to 2nd at 10mph, to third at 25, 4th at 35 and 5th at 45. I use as little accelerator as possible which my foot pretty much just resting on the pedal all the time.

This time of year your economy will be poor as the cold air is increasing the richness of your fuel mixture. During the summer i noticed the best economy. From a full tank (to the brim) i saw 150miles from the first bar, 100 miles from other bars and 30 from the final bar (yes i have actually ran out before). This makes 580miles from a single tank.

[adilmon]

Thanks for your reply.

I usually stay in the middle - up to 30km/h tops for 1st gear, 55km/h for the second, that would take me up to 3.5krpm at most I think. Always the same fuel - BP Ultimate 100.

My first service is nearing (around 12k km?), so maybe I'll tell them to check it out - but am I correct to assume these are NOT normal figures? I think a colleague's Turan burns about as much (7.5l/100)!!

I average about 72 mpg, but its a diesel.

If all the roads were perfectly flat, the best MPG is usually at the rpm where the engine hits maximum torque (for non-turbo engines). The Variable Valve timing on Aygo petrol engines is great, because it allows at least 75% of Maximum torque at almost all engine speeds

Here are the Torque Curves for the Petrol and Diesel Aygo Engines

petrol

diesel

I suggest you change gears at a 4500 rpm and see what effect it has.

Best mpg is about balancing road conditions, with revs and load on the engine. My little gadget makes this easy by simultaneously displaying Miles/litre, %engine load, rpm, and mph.

Quick example: my turbo diesel Aygo, even though best torque is at 1750 rpm, the turbo noticeably spools up by the exhaust gases from about 2000 rpm, so it’s more efficient to drive up inclines at approx 2300 rpm

[Gryzor]

Hmmm, thanks, that's very interesting and educational. However, in the graph you attached (always wondered!), max torque is achieved at 3600rpm, not 4500rpm? If it is so then I'm near it. If you insist on 4500 (do I not get something?), then I'll have to try; in any case job pays for my gas so I don't really care financially speaking... I can afford an experiment or two!

If I push it and start changing gears at 4500rpm, what other effects will that have on the engine's behavior?

Thanks again, very valuable advise...

[adilmon]

Hmmm, thanks, that's very interesting and educational. However, in the graph you attached (always wondered!), max torque is achieved at 3600rpm, not 4500rpm? If it is so then I'm near it. If you insist on 4500 (do I not get something?), then I'll have to try; in any case job pays for my gas so I don't really care financially speaking... I can afford an experiment or two!

If I push it and start changing gears at 4500rpm, what other effects will that have on the engine's behavior?

Thanks again, very valuable advise...

I meant when accelarating to motorway speeds: By changing from 3rd gear to 4th gear at 4500 rpm, 4 th gear begins working nearer to maximum torque and the load on the engine per rpm is reduced. This is even more significant when changing from 4th to 5th because the drag forces (mostly air) are increase greatly at higher speeds.

When slowing down, try to keep the car at the lowest rpm possible. This means no fuel will be supplied to the engine since the forward momentum of the car will keep the engine from stalling. I often roll up to traffic lights on a dual carriageway in 5th gear until about 30mph

Natuarally, all this effort comes to nothing if the tyres are below recommended pressure. :)

[hora]

"30 from the final bar (yes i have actually ran out before). "

Perfect. So I know Ive got 30miles before its vapour.

[Jan van de Wouw]

That's about 39mpg (imperial) as far as I can see...

Since you're using http://www.spritmonitor.de/en/ you can switch the sort of data input under "user data".

There's also an option for using miles, imperial gallons (and US gallons) and British Pounds as units...

[Gryzor]

That's about 39mpg (imperial) as far as I can see...

Since you're using http://www.spritmonitor.de/en/ you can switch the sort of data input under "user data".

There's also an option for using miles, imperial gallons (and US gallons) and British Pounds as units...

Yes, I know, but I'm from Europe :D

Anyhow, just switched it, it's indeed an average of 39mpg (Imp.). Best fueling was 45... I think I'm going to report it after all...

[Gryzor]

Ok, so I went for my 1st year's service (€120 I think), and I reported the high fuel consupmtion I've been getting. They checked it and, sure enough, they found that the oxygen sensor (? sorry, don't know the english term) was faulty, so they are replacing it today. Now, I guess this thingy is what arranges the fuel/air mix, so maybe it wasn't allowing enough air, and fuel did not burn so well, so the engine needed more of the mix (or maybe the opposite? Too much air leading to fast consumption?). WHat I'd like to know is, will the new sensor make a difference in the car's behavior with regards to speed etc?

By the way, I also reported other little problems I've been having: squeaking seat (they ordered a new one - what a waste, instead of fixing what's making the sound, throwing away the seat...), broken alarm button (replaced), passenger's compartment lid opening (fixed, they knew about it...), and also noise from the front right column plastics and rear plastic around the speaker, when music is playing. For some reason, they changed the entire Speakers! I'm just mentioning all these as a note of the problems I've found with my car.

Cheers

Themis

[adilmon]

Now, I guess this thingy is what arranges the fuel/air mix, so maybe it wasn't allowing enough air, and fuel did not burn so well, so the engine needed more of the mix (or maybe the opposite? Too much air leading to fast consumption?). WHat I'd like to know is, will the new sensor make a difference in the car's behavior with regards to speed etc?

Fuel:air ratio is important because it is the measure of getting the most kinetic energy from each combustion cycle. Too rich and your wasting fuel out of the exhaust. Too lean and you’re wasting the cc of your engine because there’s unused oxygen in the cylinder, which means you’ll have to rev higher for the equivalent speed if the Fuel:air ratio was ideal (also refered to as the stoichiometric ratio)

If there is too much oxygen in the exhaust the ECU corrects the fueling

Some vehicles deliberately increase the volume of fuel:air when the engine is cold (auto choke) or adjust the fuel:air ratio to stop the pistons head melting (the extra un-burnt fuel absorbs some heat)

Now the oxygen sensor has been replaced, the ECU can make more accurate calculations. You should find that mpg increases. If it was running rich, you shouldn't really notice much power increase. If it was running lean you will notice a power increase to its full potential

:) happy motoring

[Gryzor]

Thanks so much for your reply, much, much appreciated! I guess I should have asked them which was the case - now I don't know :)

Given that the differences were pretty big (7.5l/100km instead of 4.5) I guess there will be *some* change, though I don't know in which direction.

But thanks again!

T

[Gryzor]

Darn...

So they changed the sensor (L sensor, they called it). I took a trip to the north of Greece, a total of 1000km on national roads. Consumption had done down to 5.1l/100km, which is still way above the 4l/100km that Toyota gives for out-of-city trips.

This lased only for one full tank. Next tank - went up to a whopping 7.6l/100km, same as some of my friends' SUVs. As I'm typing this my Aygo is sitting at Toyota for a seat change (squeaking be gone!), so they'll take another look. Though when I showed the mechanic the consumption rates as shown at spritmonitor.de, he looked very, very puzzled...

Would I be so unlucky as to get two faulty sensors, or would something else affect consumption so dramatically?

Cheers

Themis

[Gryzor]

Aaaaall right, just talked with the technician in charge. He said he did not find anything wrong; that he spoke to Toyota Greece and they told him that the values that Toyota gives are calculated on a race track and do not reflect real conditions, hence my consumption rate is to be expected, depending on fuel and driving conditions.

I told him that the guy who said that must go have a talk with their corporate lawyer unless the official position is "yes, we lie about consumption rates, they're totally meaningless". And, further, that no way of driving or fuel can justify a difference of even almost 100% (highest value I've recorded, 8.09l/100km (that's 34.92mpg, according to http://www.eforecourt.com/l_100km_mpg_convert.htm , Imperial gallon)). And, further, how come when they changed my L-sensor my mileage increased to 52.4mpg (5.39l/100km) and then shot up to 7l/100km (40mpg) again? And how on earth my colleague's Turing burns as much?

So now I'm going to talk with Toyota. He gave me an email at the Toyota factory and he's also going to give me an email in Japan, but I'm also contacting Toyota Greece directly, as he suggested.

Now, I'm asking you, am I wrong to further pursue that?

Thanks,

Themis