what's with my gas tank?

[alberta_gamer]

OK, normally, my car does slightly better than 10 km/L on the highway and quite a bit less than that in the city. So imagine my surprise today when I could only put 18 L in my tank with 282 km since the last fill. I was expecting 28-30 L to fill it given I've done mostly highway since the last fill.

And yes, I thought the pump was shutting off in error at 18 L, and it came out a bit to confirm it was indeed full. My tank gauge is flaky, but I get around that by not trusting it and resetting the odometer counter at each fill and not letting it go over 300 or so. Hence, I'm never sure how much (was) left in the tank until I fill it to full.

My theories:

- is the gas pump inaccurate to that degree?

- did somebody put water into my tank (for whatever reason - but the car runs great so I rule this out)

- is the tank split into two compartments and one is somehow sealed off?

- is there air in the tank to that extent?


Should I even be concerned?


Thanks for your time.

:confused:

[revelations]

Years ago I had something similar happen to me on the bike.

Normally I got 125kms on the bike before the fuel light came on but this one time I got 185kms, which shocked me because I had a passenger the whole time and we were bumming around the city.

Chalk it up to a conspiracy by the gas companies to sell you more of a less potent product ..... and sometimes make a mistake in the formulation of the fuel that permits increased mileage

:nut:

[Sugarphreak]

...

[AE92_TreunoSC]

Tail winds and downhill decent can easily boost a half tank to huge mileage gains.

It's why its best to average fuel economy.

Most people ignore the mileage they get when its a head wind heading into the mountains.

[Sugarphreak]

...

[DeleriousZ]

Blockage in your gas vent hose? What does your flakey gas gauge read after the fill?