95 Mazda 626 - Gas tank fills up to half way

I purchased this vehicle in July and the previous owner told me that there had always been this problem with the gas tank only filling up half way but she never worried about it. After owning the car for 8 months now, I’d really like it if I didn’t have to do so many trips to the gast station. Any ideas on what the problem might be?

One possibility would be that the gas gauge or the fuel level sensor is defective and that your tank really is full when the gauge says half full and half full when it says empty. Unfortunately I can’t think of any simple way to check that other than driving until you run out of gas, then seeing how much gas you can put in the tank. Other than that, it could be some sort of problem with the filler pipe not venting air out of the tank once the tank is half full.

On a 95, the weird problems that some people have getting fuel into a few 2000 and later cars shouldn’t apply. Those problems are presumably caused by emission control hardware you won’t have.

Is there a free, no effort, repair? Nope.

Why, other than the prior owner’s comment, do you believe it is only filling up half way?

When the gas gauge is at empty, I fill it up, paying only $12.00, and leaving the gauge pointing at the half way mark. It’s possible, like vtcodger2 said, that it’s filled all the way but the gauge or fuel level sensor is defective… But how would I know?

Here is the test. Put a gallon container of gas in the trunk (full of gas). Now, drive until you run out of gas. Put your spare gallon of gas in the tank, drive to the gas station, see how many gallons you can put in. If it is close to 15, (which it think is the tanks size) then the problem is in the gauge or the gauge sender. If you can only put 7 or 8 gallons in, then there is something wrong with the tank.
There was a story about a situation like this, when the owner had the tank examined, they found 1/2 the tank was filled with drugs.
BTW don’t make it a habit to run your gas tank dry, that is not good for the fuel pump. But one time shouldn’t hurt anything.

You know that your gas tank is full because the gas pump nozzle automatically shuts off when no more fuel will go into the gas tank. The gas pump doesn’t care what your gas gage reads.

Not always true. If the gas tank is not venting properly during fueling, then the pump will shut off prematurely.