Looseing fuel while car is sitting

[HamzGTT]

I have a 99 Caldina GTT the car has pretty much been sitting for 3 weeks except for a couple of times i have taken it out for a general drive have covered about 110km during this an have noticed the fuel has gone down to a 1/4 of a tank of gas over the period of time. When the car was sitting for a week it went from full to 3/4 full and all i did was start the engine for 5 mins on one day.

I know this might be a bit of a shot but could there be a problem with the evaporating system. I have gone right through this car bumper to bumper looking and smelling for fuel leaks and not a thing. When it comes to fulling the car i remember that all my other cars would have a vacume effect in the tank when i realesed the fuel cap but not with my toyota.
any suggestions.

(edited to make more clearer)

[Mr Revhead]

so have you lost 3/4? or 1/4?

i would say its just the normal awesome non accuratness of toyota fuel gauges

like my corolla, i can get 300ks in the first 1/4 tank
but only 300k from the last 3/4

[xsspeed]

I think its more widespread than just toyotas, happens in pretty much any car I've owned.

I rekon they just use a height/depth level and dont account for the volumetric changes in the tank. My theory anyway, never bothered to figure it out properly

[HamzGTT]

Have lost 3/4 total so far but lost 1/4 in the first week of sitting around. being that its a turbo vehicle i have my turbo timer set for 40sec after ignition off so in saying that would the fuel guage settle in that time frame since the vehicle is settled and there is still power goin to the guage and being at this time i have just fulled up the car?

[HamzGTT]

Im just getting worried as the price of fuel goes up again and my reduced hours at work im starting to look at everyting that costin money and when i see a fuel guage start dropping when pretty much nothing happens it starts to make you wonder.

[Mr.Phreak]

Wasn't a hot day when you parked it up, and a cold day when you checked again?

[strx7]

My Surf seemed to do this. It also seemed to have alot of pressure build up in the tank. what I put it down to what the pressure build up in the tank effects the bouyancy of the fuel level sender float.

[sergei]

Did actual fuel level dropped?
What I've seen is that friction that supposed to hold needle at position when ignition was off was not strong enough and needle was dropping down slightly (due to gravity). When you would start the car it would go back up.
I also seen it go other way round on OFF it would go to full but when ignition ON it would drop to the right level.

Never rely on fuel guage on how much you have fuel, it is only approximation, best way is monitor fuel usage and use odometer to judge how much fuel you have left (besides it sits on above F and below E for over 100km without moving , half way is about 40% left, and between first quarter and last is not half, but closer to 30% fuel).

[mjrstar]

i recall an issue we had with an aircraft oil tank level sensor, basically the float had a pinhole in it and over about a week the level went down slowly, but still showed full on the dipstick.. could be something like this? but unlikely i'd say

[Jazza]

Got any maori mates/neighbours borrowing gas? (Yes, im part maori, not racist )

Might have a leak and its evaporating, is that possible?

[escortman]

rip the turbo timer out as well

[HamzGTT]

Got any maori mates/neighbours borrowing gas? (Yes, im part maori, not racist )

Might have a leak and its evaporating, is that possible?

I live with natives of New Zealand and no I dont think that my petrol is being taken without my permission.

LOL very funny thought though (Was kinda wondering if someone would say this)

[HamzGTT]

Wasn't a hot day when you parked it up, and a cold day when you checked again?

I heard of this and have since only filled my car in the morning

[Jazza]

Never know - thats why my old man always screams when the lawnmower is out of gas, same with the boat, same with his runaround, same with my brothers car Im a poor student!

[Bling]

Somehow this thread jogged my memory along the same lines..... a local member had a similar issue 4 years ago

viewtopic.php?t=30045

End result being, yes infact someone was stealing his fuel

[CelicaGT8]

Try takeing off the fuel cap for a day or two, or drill a small hole in it so it doesnt build up pressure or leak fuel.

Or do you have a dodgy mate that always has a hose and a fuel container in his car when he comes over haha

[Mr.Phreak]

or drill a small hole in it

[Mr Revhead]

how would that help?



have you actually confirmed that there is less fuel?

[Jazza]

Fill it, count the litres that go in.

Later that day

Syphon it out, count the litres that come out...


Then just funnel it back in, least youll know if its USING/LOSING gas or whether its just a fubar fuel gauge