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Fuel Computer Acuracy


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Hi All

new to this Having owned An Alfa for a couple of years (need the reliability)

Anyway to my question. (well i have 2)

This on board fuel computer. MY 53 Avensis T4 1.8 says an average of 56-59 mpg. I mainly use it for work and cover 25 miles a day mainly on a dual carraigeway. I expected it to be quite economical but this is amazing. My Alfa gave me 36MPG and i thought that was good.

On filling up recentley for a trip away i covered 210 miles then filled up again with around 25ltrs. divide this by 4.4lts per gallon, i make it around 36 MPG Whats going on with the computer It was telling me 59MPG, Can it be callibrated. On filling up it said i would have 440 miles per tank which gives me an average of 32 MPG however, assuming its a 13.6 gallon tank or 60 ltres (does it discount a 10 ltr reserve? this would then return me an average of 38 MPG ;) Are you still following people. ;)

If anyone would be so kind as to reply with some advice i would be greatfull.

My second question is I have an annoying boot rattle wich i think is the boot lid. can the lock be adjusted to close more tightly preventing he lid from rattling.

Paul :rolleyes:

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I have 03 Avensis T3-S and the computer shows 514Miles at fuel up but it does 330miles per tank.

330miles even when the tank is filled from completely empty. I even had the clutch changed recently. The computer shows 39MPG

You filled up 60ltr + 25ltrs that should have given you a total of 467miles in total. But thats only according to calculations of my car consumption.

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I have a 55 Plate (06) T3-S 1.8 and I have to say that my Fuel Computer is pretty much spot on. A full tank generally registers 445 miles on the display which equates to approx 34.2 mpg. In real terms I average anything between 34mpg and 38 mpg when I record it manually and is dependent on driving style and conditions.

I think claims of 45 mpg plus are pretty much exagerated although I reckon 40mpg is acheiveable is conditions are right.

TeyaDog

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I have a 55 Plate (06) T3-S 1.8 and I have to say that my Fuel Computer is pretty much spot on. A full tank generally registers 445 miles on the display which equates to approx 34.2 mpg. In real terms I average anything between 34mpg and 38 mpg when I record it manually and is dependent on driving style and conditions.

I think claims of 45 mpg plus are pretty much exagerated although I reckon 40mpg is acheiveable is conditions are right.

TeyaDog

I agree but my computer indicates an ave of between 55-59MPG massivly unrealistic. Would love to know if it can be recallibrated.

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Hi All

new to this Having owned An Alfa for a couple of years (need the reliability)

Anyway to my question. (well i have 2)

This on board fuel computer. MY 53 Avensis T4 1.8 says an average of 56-59 mpg. I mainly use it for work and cover 25 miles a day mainly on a dual carraigeway. I expected it to be quite economical but this is amazing. My Alfa gave me 36MPG and i thought that was good.

On filling up recentley for a trip away i covered 210 miles then filled up again with around 25ltrs. divide this by 4.4lts per gallon, i make it around 36 MPG Whats going on with the computer It was telling me 59MPG, Can it be callibrated. On filling up it said i would have 440 miles per tank which gives me an average of 32 MPG however, assuming its a 13.6 gallon tank or 60 ltres (does it discount a 10 ltr reserve? this would then return me an average of 38 MPG ;) Are you still following people. ;)

If anyone would be so kind as to reply with some advice i would be greatfull.

My second question is I have an annoying boot rattle wich i think is the boot lid. can the lock be adjusted to close more tightly preventing he lid from rattling.

Paul :rolleyes:

Re: Computer - My computer is always pessimistic by 2mpg or so (Manually Calculated Tank vs Average) but you have to remember that the solid figure given is an average of all of your MPG not just your current tank. If you want your tank MPG you should reset it when filling up and check it on your next fill up.

The range mileage is a rubbish readout really, usually stating the amount left in reserve as well and, once the fuel light comes on, in my car the range mileage counts down far quicker than the trip. I think this range is dependant upon the average of the current driving style and I find that this corrects itself up/down fairly often.

Incidentally, does anyone know how many litres/gallons are in the reserve tank?

Re: boot rattle - there will be some star-type bolts under the plastic slam panel, loosen and adjust the lower catch which is hidden beneath. Do this only slightly as you will be altering the panel alignment as well.

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Hi All

new to this Having owned An Alfa for a couple of years (need the reliability)

Anyway to my question. (well i have 2)

This on board fuel computer. MY 53 Avensis T4 1.8 says an average of 56-59 mpg. I mainly use it for work and cover 25 miles a day mainly on a dual carraigeway. I expected it to be quite economical but this is amazing. My Alfa gave me 36MPG and i thought that was good.

On filling up recentley for a trip away i covered 210 miles then filled up again with around 25ltrs. divide this by 4.4lts per gallon, i make it around 36 MPG Whats going on with the computer It was telling me 59MPG, Can it be callibrated. On filling up it said i would have 440 miles per tank which gives me an average of 32 MPG however, assuming its a 13.6 gallon tank or 60 ltres (does it discount a 10 ltr reserve? this would then return me an average of 38 MPG ;) Are you still following people. ;)

If anyone would be so kind as to reply with some advice i would be greatfull.

My second question is I have an annoying boot rattle wich i think is the boot lid. can the lock be adjusted to close more tightly preventing he lid from rattling.

Paul :rolleyes:

Paul,

The trip computer in mine and others I have checked have been deadly accurate, my T180 reads about 0.5mpg low unfortunetly usually on the the wrong side of 40!

Yours must have a problem and is probably a sensor rather than calibration because its too far out. good luck getting it fixed, not had much with mine.

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The reserve is VERY generous, 3 gallons I think, from the time the light comes on, I can still easily get 80 miles or more until my bottle goes and I have to fill up, even then, I can still only get 55l in the tank! My trip computer have never been very accurate compared to the pen and paper method, usually quotes me 4-5mpg better.

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  • 3 weeks later...
The reserve is VERY generous, 3 gallons I think, from the time the light comes on, I can still easily get 80 miles or more until my bottle goes and I have to fill up, even then, I can still only get 55l in the tank! My trip computer have never been very accurate compared to the pen and paper method, usually quotes me 4-5mpg better.

Do you get any further warnings as the fuel level get critically low? I have heard someone with an Aygo getting frequent beeping. I am just curious cause I generally fill up quite soon after the light comes on.

Cheers

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  • 4 years later...

On board computers are reknown for being optimistic (referring to all makes not just Toyota). However having had my 2010 1.8 vvti auto estate for a few months now am please to say my readout is extremely accurate. I have been doing brim to brim checks and it confirms the on board computer read out as being accurate at 37.7 over around a dozen or so refills. Have yet to get to a situation where the light comes on so can't comment on the reserve. Petrol prices vary so much in the area that I top up anytime below half a tank If passing a low priced station.

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Have a 2.2 d4d. did a round trip to the north east last week and got nearly 70mpg...... think it was about 68 in the end. I couldnt beleiev it. I was avereging about 70mph all the way as the traffic was pretty heavy.

On average doing combined Im currently on 52mpg. I think thats pretty good for a 2.2. Although I drive it pretty conservatively mostly. It certainly goes down when i put my foot down

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on board computer is always optimistic, so brim to brim calculations would be my recommendation,

W.R.T boot rattle, in most cars, you can adjust the rubbers, but not so in the Avensis, so what I have done is added a bit of extra rubber material on top of the existing rubber, about a few mm thick, essentially pushing the boot lid up hence no play for the boot lid to rattle. but what I have found is that the parcel shelf isn't the best either, so on big bumps that rattles a bit, but I can live with it since I try and avoid pot holes as much as I can, safely

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I've had my 52 plate 1.8 vvti for a grand total of about 10 days.Mind you,my W plate 1.8 7a-fe thats done me for the last year is still parked in the drive,cant find the bloody logbook for that final run to the scrappys.lol.

Well I reset the fuel computer when I picked up and it's settled at an avg of 39-40mpg which i'd say was pretty spot on.The range does appear to countdown inline with the trip meter but I've noticed that when it gets real low it jumps to 400+ miles.

As for the reserve it's definitely generous.I've got a 40 mile round trip to work n back daily and have done it two days on reserve (absolutely skint at the time) before refueling.

In fact I got incredibly blase about running about on reserve till the needle was clear below empty - but I wouldnt recommend it.lol.

Yesterday I checked the range when I saw the reserve light come on and it said 125 miles which I'm not buying.

I'll stick to zeroing the tripmeter every time i fuel up n doing the mental arith in my head to tell me how many miles I got !!!!

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i have a 2003 2.0 D4D T3-S Estate 140,000 of which i've done 100,000 in the last 6 years.

The fuel computer is 15% to 25% optimistic indicating 60 to 70mpg when it is actually 50 to 55 mpg.

50 40 .

40 35

My girlfriend has a fabia and that's pretty much spot on.

Does average per tank 35 to 45 mpg driving carefully - never stopping - 35 all town driving - 45 with 150 miles of motorway at 50 - yes 50 mph. Speed costs mpg because wind resistance is the killer here. 45 mpg is 10 miles per litre giving a 600 mile range if you have the bottle to chance it.

I am skint therefore I drive reeeel slow. (should have got a petrol rather than a diesel - nobody ever tells you that of course).

The Avensis is a fantastic car - very classy - very safe - heavy though - 3 sets of front discs - 2 clutches including 1 DMF - 2 brand new clutch mastercylinders (and 1 clutch pedal!) - EGR cleaned twice so far - one set of front struts - serviced properly, belts, filters, including pollen, and only toyota Oil filters and Wiper Blades. Taxi drivers must know something.

I have a good small garage. He's cheap and i trust him. I couldn't afford a car like this without him - he has a good spanner man and a good tech man.

I've also had it converted to HIDS and all LED lights (bulbs really awkward and some impossible) - after market cruise fitted. I am fussy though and don't like driving it with ANY faults.

Takes loads impressively, 4 people plus 100kg of deadweight handled easily through high speed and wet twisty mountain roads in south wales.

It is a 60 litre tank - the light comes on when there is about 10 litres left - depending on whether up or down hill. Use fully synthetic Oil ALWAYS and often. Mine still drives like NEW. Everyone who gets in it is impressed even though it's nearly 10 years old and been round the planet nearly 6 times with 80% of that town driving.

Concerns:

1. Key is a worry - 1 of the 3 buttons recently fell off and i'm trying to repair it without spending nearly £200 with the main dealer.

2. It's only now worth £800 ish, going down, am nearly 60 and earn very little - so i am going to die driving this thing - and it's going to be impossible to replace in the case of accident.

3. EGR valve because of the way i drive.

Anybody knows what to do about the key?

Do these engines have swirl flaps?

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  • 2 weeks later...

Hi All

new to this Having owned An Alfa for a couple of years (need the reliability)

Anyway to my question. (well i have 2)

This on board fuel computer. MY 53 Avensis T4 1.8 says an average of 56-59 mpg. I mainly use it for work and cover 25 miles a day mainly on a dual carraigeway. I expected it to be quite economical but this is amazing. My Alfa gave me 36MPG and i thought that was good.

On filling up recentley for a trip away i covered 210 miles then filled up again with around 25ltrs. divide this by 4.4lts per gallon, i make it around 36 MPG Whats going on with the computer It was telling me 59MPG, Can it be callibrated. On filling up it said i would have 440 miles per tank which gives me an average of 32 MPG however, assuming its a 13.6 gallon tank or 60 ltres (does it discount a 10 ltr reserve? this would then return me an average of 38 MPG wink.gif Are you still following people. wink.gif

If anyone would be so kind as to reply with some advice i would be greatfull.

My second question is I have an annoying boot rattle wich i think is the boot lid. can the lock be adjusted to close more tightly preventing he lid from rattling.

Paul rolleyes.gif

I have exactly the same problem.. 1,8 vvti (2003) and my computer is also too optimistic. Average in town(with heavy foot!) should be around 30mpg(calculated) but my comp shows 48-55mpg!! Did u find out what was the problem? 4 days ago i have filled up the tank with 40liters of petrol and comp showed range-432miles, but i actualy did only 310miles :( . This comp just makes me sick. If the comp is alrite what sensor could be faulty? I have noticed that comp shows correct numbers only for a 20-30 miles after filling but than it goes back to unreal numbers :( . Any advices lads???

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  • 2 weeks later...

filled up the tank to full 2 days ago.. average mpg reset it self but after 10 miles of driving in town it shows 65mpg!! Aaaahhhhrrr it killin me. Does anybody what could be wrong pleasssssssssseeeeeeeee?!?!?!?

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Mine tends to read between 55- 65mpg ..... if I work it out from receipts, I get about 55mpg, so I guess they are a reasonable indication ... (give it to my wife for a dy and it's down in the 30's :nono: )

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