Likely, a fuel pump can be damaged over time when gas is near the E mark. That's because the fuel pump in most modern cars is inside the gas tank and depends on fuel to cool it, as well as lubricate its internal parts. With lower fuel levels, the pump will have less liquid to cool it and prevent it from overheating — wearing down quicker. If you run your car below a quarter tank of gas on a regular basis (some sources suggest as little at 1/8th), studies in the auto industry note that it can reduce the lifespan of your fuel pump by up to 25%+.
Fuel pumps damaged by low fuel will usually be replaced in the $400 to $1200 range, based on make and model. Typically, luxury auto brands like Audi or BMW could cost over $1,000 for this service compared to mainstream vehicles such as Honda or Ford which can be a bit lower. The time it takes to replace a fuel pump is typically 2–3 hours making the bill add up quickly. Avoidance of low fuel conditions can thus prevent hundreds in repair costs over the vehicle lifetime.
In short, a fuel pump works by transferring gasoline from the tank to the engine at an even level of pressure; typically around 30-60 psi depending on your car. When fuel is low then the pump must work harder to achieve this pressure which increases electrical current draw and also can cause heat. This stress causes the internal components of the pump to wear out over time and thus it fails prematurely. The Pro-Street Performance guide quotes a study by AAA which indicates that 10% of the time, investigated fuel pump failures could be directly attributed to low tank levels in fact frequent operation on minimum gas is an offshore signal with regard to potential gasoline pump lifespan.
Automotive guru Ferdinand Porsche is credited with observing, "If one does not fail at times, then one has never challenged himself." Although driving a vehicle to its limits is exhilarating, so too it comes added strain on the fuel pump that just incremental miles slowly wears out this critical component. Delays in fuel stops are incredibly shortsighted when weighed against the costs of irreversible damage to our pocketbooks after paying for too many failed replacements.
To sum it up, keeping more than a quarter tank of fuel not only saves you from having to replace the pricey fuel pump but also makes your car run better. With this Fuel Pump designed to meet industry standards possible from it, those who want a no-nonsense repair that is going to be made less often will do well getting ready.