My gas gauge goes up when I am driving and down when I am idling. It can vary by as much as a quarter of a tank. How do I know what is accurate?
2007-12-05 17:28:31 · 2 answers · asked by Cynthia E 2 in Cars & Transportation ➔ Maintenance & Repairs
That's very typical behavior of gas gauges in general. Sorry, there's no such thing as an accurate gas gauge. The top half of your tank is actually larger than the bottom half, and the measurement can vary according to which way your car's tilted. It's most accurate when you first turn it on and if you're on level ground, but I recommend that you use your trip odometer instead - it's much more accurate. When I get a new to me car, I fill up at what the gas gauge says is 1/2 tank and compare that with the trip odometer and what the tank will actually hold according to the owner's manual. Of the various cars I've owned (2 compacts, 1 full-size, and 1 12-passenger van), 300 miles on the trip odometer coincided fairly well with having just over 1/8 tank left, time to fill up.
2007-12-05 17:49:57 · answer #1 · answered by The SuburbanCat 4 · 0⤊ 0⤋
The gas in the tank is sloshing towards the rear of the tank when driving and causing the float in the tank to go up which causes the gas gauge to do the same. Best measurement is while sitting still. This can be caused by a defective resistor on the gas gauge (dash unit)....we use to replace them from time to time years ago....it's a cheap part but labor may be a bit high to do.
2007-12-06 02:46:31 · answer #2 · answered by paul h 7 · 0⤊ 0⤋