Can you damage your car engine by consistently driving with very little fuel

Unlike the old mechanical fuel pumps which used to mount on the side of the engine, the pumps of todays are highly electronic and are located in the gas tank. These are precision pieces of equipment which rely on lubrication from the fuel.

By running it with a low amount of fuel it works harder because the level of lubrication and protection a fuller tank would offer isn’t there, causing more heat and resulting in premature wear. In addition, the pump will pick up dry spots as the fuel sloshes back and forth in the tank, further stressing it.

The bottom of your gas tank has a higher concentration of water, especially present due to the phasing (separation of gas and moisture) caused by ethanol fuel most people use, and dirt/debris.

The lower the gas level, the higher the concentration which will be pumped into the engine. This will cause increased wear on the fuel filters and injection system, hindering performance and damaging those systems prematurely.

However, you can damage the fuel pump. The fuel pump in a gas tank usually has a little plastic bag attached to it, driving with very little fuel will cause the fuel pump to overheat and burn the little plastic bag. When this happens your vehicle can stall and or have a really hard time starting.

The gas in your tank is fueling your car and keeping your fuel pump cooled off it just needs to be fully submerged in fuel to stay cool I would say around a quarter of a tank is the lowest you should go to avoid fuel pump issues.