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Does driving a car on a low tank of gas hurt the engine.


It can cause the fuel pump to fail prematurely. The fuel in the tank cools the pump under normal operations. It is a good idea to leave the tank at least 1/2 full.

No, but it can allow the fuel pump to overheat if you do it all the time.

Running out of gas hurts the fuel pump. Operating a vehicle on a low tank of gas is fine.

Not usually but why? You are not going to save fuel or money by waiting to fuel up. You can run out of fuel when you unexpectedly need to make a trip etc.

I once had a friend that somehow felt it was cheaper to keep the tank close to empty and to spend no more than a couple of dollars at a time on fuel. More than once I ended up bringing here fuel to where ever she ended up running out of fuel.

The fuel pump is cooled by the gas flowing through the pump, not by the gas surrounding it. You do no harm at all letting the fuel run low. None.

"You do no harm at all letting the fuel run low. None."

Maybe, maybe not.  It is not generally a big problem, but when the tank is near empty it tends to slosh around and you can pick up junk from the bottom of the tank that normally would not get picked up.  Of course running low increases the chances of running out of fuel, which can be dangerous when you are in heavy traffic in a middle lane. 

I stand by my recommendation of avoiding running low.

Didn’t we have another whole thread just on picking up the “junk in the tank”?

AL5000, UncleTurbo have it correct. It won’t hurt anything unless you run out in a dangerous area or get stuck somewhere.

Running the car on a low tank of gas does not hurt the engine. But it can cause the other problems mentioned. Besides, who wants to run out of gas in a bad neighborhood, or on a cold rainy night on a busy highway with no place to roll safely to, or in the middle of a blizzard when driving is dangerous enough as it is?

There is absolutely no benefit to driving with the tank low. None. Nada. Zip. So why take the associated risks?