Driving With A Nearly Empty Tank Kills This $1,200 Engine Part

Keeping your gas tank above quarter-full prevents costly fuel pump damage that can cost up to $1,200 in repairs from overheating and cavitation.

Published on Feb. 11, 2026

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Modern electric fuel pumps rely on gasoline immersion for cooling and smooth operation. When fuel levels drop below a quarter tank, the pump starts gulping air instead of gas, creating cavitation that can damage the pump and lead to costly repairs. AAA reports that fuel pump issues account for 12% of roadside assistance calls in 2023, and constantly running near empty accelerates that timeline. Replacing a damaged fuel pump can cost $500-1,200, depending on the vehicle.

Why it matters

Fuel pump failures from low fuel habits can be a significant expense for drivers, costing up to $1,200 in repairs. This issue is common, with 12% of roadside assistance calls in 2023 related to fuel pump problems. Keeping the tank above a quarter-full can help prevent this costly damage and extend the life of the fuel pump.

The details

Modern electric fuel pumps sit inside the fuel tank and rely on the gasoline to keep them cool and lubricated. When fuel levels drop below a quarter tank, the pump starts drawing in air instead of gas, creating cavitation bubbles that can damage the pump through overheating and friction. This leads to symptoms like whining noises, hard starting, and sputtering under load. A struggling pump can also decrease overall fuel efficiency by more than the weight penalty of a full tank.

  • AAA reported fuel pump issues accounted for 12% of roadside assistance calls in 2023.

The players

AAA

A federation of motor clubs throughout North America that provides roadside assistance and other automotive services.

Annemarije de Boer

A Los Angeles-based director and visual storyteller specializing in technology reviews and digital innovation journalism.

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The takeaway

Keeping your gas tank above a quarter-full can help prevent costly fuel pump damage that can run up to $1,200 in repairs. The weight penalty of a full tank is outweighed by the efficiency losses from a struggling fuel pump, so it's better to maintain a healthy fuel level to extend the life of this critical $1,200 engine component.