Broken gas gauge

RKGCOLE

MEMBER
2008 FORD ESCAPE
1,000 MILES

I put half a tank worth of gas into my car and after driving only about fifteen miles down the road the gas gauge was showing it was down to a quarter of a tank.
I smell no gas and see no signs of a leak anywhere. I cannot drive four miles without the gauge dropping ten or so miles. Could it be a sensor in the gauge? Or maybe in the gas tank?

1 Reply

CARADIODOC

MECHANIC
33,760 POSTS

I wouldn't assume any symptoms point to a problem until you fill the tank, then run it close to "empty". The gauges are no longer the simple, reliable assemblies that worked fine for decades. The instrument cluster on Ford products is the most "intelligent" computer on the car. For some reason, the engineers didn't feel anything other than filling the tank was a normal condition. It never occurred to them that someone might only half-fill the tank. Thanks to all the computer controls, including Traveler Computers, (miles to empty, etc.), The gauges are recalibrated each time the fuel level changes suddenly. The actual reading or the rate of change may not match what is actually taking place.

Also be aware that on some car models a properly-working fuel gauge is not linear. I suspect that is because they wanted to used a float and level sensor that was already in production for a different model, rather than design a new one specifically for a different gas tank. On some of these, the gauge stays near "full" for the first 150 miles, then drops to "empty" over the next 150 miles. I have two of those vehicles. The tanks hold 18 gallons. When empty, if I add only eight or nine gallons, the gauges will read almost "full".