Question on fuel gauges and tank size

Mister Jingles

Just want to explain a something that has me scratching my head with curiosity.

Two large family sized petrol cars, a 1.8 Mondeo and a 1.6 Avensis both 2004.

The Mondeo's petrol tank is 58 liters while the Avensis is 60 liters.

Why is is that when I put 20 quid of petrol into the Mondeo from near empty the fuel gauge only goes to quarter of the way while with the Avensis also from near empty on 20 quid goes a lot closer to the halfway mark but yet the Avensis tank is two liters bigger ?

Is this just a case of how inaccurate fuel gauges can be ?

Jesus.

Mister Jingles wrote: »

Is this just a case of how inaccurate fuel gauges can be ?

Pretty much

Mister Jingles

I've always known that they can be off a bit but it seems a lot in this case.

Bpmull

Mister Jingles wrote: »

I've always known that they can be off a bit but it seems a lot in this case.

Does it drop back a bit after you've driven it a few miles some do that.

colm_mcm

Toyotas are pretty much often like that.
Avensis has a range indicator on the trip computer though.

CJhaughey

My Avensis gauge doesn't move from full until there is at least 160 miles done.
It all depends on how the sender unit is arranged in the tank, some can be more accurate than others, or calibrated better ?

Stheno

Yeah same with our two cars

TrailerBob

Toyotas are known for their rapid drop from half full on the gauge. Just something you get used to. Mine does it too

10-10-20

Because the tank isn't square, it's rounded at the tops and bottom. The sender is linear and returns the relative level,so hence the top-most or bottom-most parts may deplete at a quicker level. Think of a funnel.

Mister Jingles

Bpmull wrote: »

Does it drop back a bit after you've driven it a few miles some do that.

Not really, it is very sensitive though when it's parked with one side on the path and the other on the road at an angle. But that's understandable.

I also find that the warning light comes on quite earlier again closer to the quarter mark then the red mark.

Mister Jingles

10-10-20 wrote: »

Because the tank isn't square, it's rounded at the tops and bottom. The sender is linear and returns the relative level,so hence the top-most or bottom-most parts may deplete at a quicker level. Think of a funnel.

Which is this the avensis or mondeo ?

Mister Jingles

colm_mcm wrote: »

Toyotas are pretty much often like that.
Avensis has a range indicator on the trip computer though.

Yeah zetec and lx mondeos were deprived of that, only available to ghia and titanium specs.