Fuel gauge theory

[Ron Gamma]

Here is a theory.

If I use my car for short journeys the fuel gauge shows usage quite normally.
If however, I use my car for long journeys (i.e Kent to Cornwall) the fuel gauge is for example only 1/4 full when I get there. Next morning I go to use the car again and the fuel gauge says less than 1/4 full.

Could it be that the exhaust system heats the fuel tank and contents indirectly thereby increasing the temperature of the sender float and causing it to ride higher in the fuel at the end of the journey?
As it cools down overnight it then sinks back to normal and shows the true fuel usage.

Discuss.

 

[tim west]

Could be the Cornish Pixies playing around with your gauge?

 

[Spark123]

Isn't it dangerous to heat the fuel tank? Don't exhaust pipes normally go around the fuel tank?

 

[2scoops0406]

Here is a theory.

If I use my car for short journeys the fuel gauge shows usage quite normally.
If however, I use my car for long journeys (i.e Kent to Cornwall) the fuel gauge is for example only 1/4 full when I get there. Next morning I go to use the car again and the fuel gauge says less than 1/4 full.

Could it be that the exhaust system heats the fuel tank and contents indirectly thereby increasing the temperature of the sender float and causing it to ride higher in the fuel at the end of the journey?
As it cools down overnight it then sinks back to normal and shows the true fuel usage.

Discuss.

Odd that my tank is always slightly over 1/4 full the next morning, though I have an awful taste in my mouth, can can't think how that could be

 

[breezer]

might be the cold at night, petrol contrcats when cold