Corolla 2005 1.6l Petrol

[Justas]

Hello,

I have corolla 2005 1.6l petrol for a year now and i have noticed that trip computer is showing nonsense and i am talking not about exact consumption but about difference between mpg and L/100km. So currently my mpg is 34.9 and if I change setting in trip computer to L/100km it should be 6.74 l/100km, but it shows 8.1 l/100km. how is this possible at all? i do understand that strip computer might show not exact readings, but this is trip computer software programming mistake. Funny thing is that i cant find anything on the internet about it, so was thinking maybe i am the only one with defective trip computer. Thanks for replays

[oldcodger]

No, its normal for this old type.

Sometimes the readings can be way off, sometimes quiet close.

Just not worth bothering with.

The only way to be sure is to fill up to the brim, reset the trip odo and check the mileage /consumption next time you fill to the brim again.

My 1.6 gives about 40-42 mpg in summer and 38-40 in winter, mixed mway/town driving

[Justas]

Well you did not get what i wanted to say. what i wanted to say is that my mpg is currently 35, and if i switch trip computer to l/100km it shows 8 L/100km right now. i am talking not about how accurate trip computer is but i am talking that if you switch between imperial and metric the numbers do not add up. lets do some maths. For example 35mpg (that is being shown tight now) converts to 6.72 l/100km and metric 8L / 100km (that is being shown right now) converts to 29.4 MPG. Numbers simply do not add up. I would be appreciated if someone would post there trip computers metric and imperial average (L/100km and MPG) 

Update:

Messurements do add up. Simply i was calculating useing US galons and not imperial ones.

[oldcodger]

No, sorry , did not miss your point, just assumed that being as it been said many times in the forum, its not an accurate system generally.

Just got my readings  39.1 mpg  7.2L per 100k  13.8km / L  -  which seem to agree with each other  , but will let you check  that out .

The other thing that  I experienced on this corolla and my old 1.8 Avensis is that the speedometer always records about 2-3 mph Higher at 30 and about 4-5mph at 70, so would assume that also has a misleading effect on the true miles done  / per gallon.

Using a gps app on your phone will soon show that up. Not sure if its a wheel /tyre thing or just that they have deliberately set it high to give you a margin for the speed cameras ??

 

[FROSTYBALLS]

16 minutes ago, oldcodger said:

The other thing that  I experienced on this corolla and my old 1.8 Avensis is that the speedometer always records about 2-3 mph Higher at 30 and about 4-5mph at 70, so would assume that also has a misleading effect on the true miles done  / per gallon.

Using a gps app on your phone will soon show that up. Not sure if its a wheel /tyre thing or just that they have deliberately set it high to give you a margin for the speed cameras ??

Speedometers are designed to be optimistic to comply with legislation -

In the UK, the speedometer must never show an indicated speed less than the actual speed.

The indicated speed should never show more than 110% of the true speed. Additionally for all actual speeds between 25 mph and 70 mph (or the vehicles' maximum speed if it is lower than this), the indicated speed must not exceed 110% of the actual speed, plus 6.25 mph.

For example, if the vehicle is actually travelling at 50 mph, the speedometer must not show more than 61.25 mph or less than 50 mph.

[Heidfirst]

2 hours ago, oldcodger said:

3 hours ago, Justas said:

Update:

Messurements do add up. Simply i was calculating useing US galons and not imperial ones.

thought that might be it 

The other thing that  I experienced on this corolla and my old 1.8 Avensis is that the speedometer always records about 2-3 mph Higher at 30 and about 4-5mph at 70, so would assume that also has a misleading effect on the true miles done  / per gallon.

I understand that the speedo & the odometer are not linked so although the speedo over reads it should not affect the odo.