Everyone’s been there at some point: you’re watching the fuel gauge, hoping you can make it to the next station, when suddenly the tank runs dry. While it might seem like nothing more than an inconvenience, running out of gas can actually cause damage to your vehicle in ways most drivers don’t realize.
Knowing what happens inside your fuel system when the tank is empty will help you avoid costly repairs and keep your car running reliably.
What Happens When You Run Out of Gas
Modern vehicles rely on a steady flow of fuel to keep the engine running smoothly. When the tank runs dry, air gets pulled into the system, disrupting combustion and causing the engine to stall. In some cases, you may have to crank the engine several times after refueling to get it started again because air pockets need to work their way out of the lines.
While one incident may not destroy your car, repeatedly running out of fuel or driving with the tank near empty can create long-term problems.
Strain on the Fuel Pump
Your vehicle’s fuel pump sits inside the gas tank and relies on fuel for both cooling and lubrication. When you drive on empty, the pump has to work harder to draw in fuel and stays exposed to heat without the benefit of constant cooling. Over time, this additional stress can cause the pump to wear out prematurely or fail entirely.
Replacing a fuel pump is significantly more expensive than simply keeping your tank filled. By avoiding frequent low-fuel situations, you extend the pump’s lifespan and reduce the chance of an unexpected breakdown.
Sediment and Contaminants in the Tank
Tiny particles of dirt, rust, and debris naturally settle at the bottom of your fuel tank over time. When the fuel level gets low, the pump begins drawing from the bottom, sending those contaminants through the fuel lines and into the filter.
While your fuel filter traps much of this debris, repeatedly running the tank near empty increases the risk of clogging. A clogged filter restricts fuel flow, reduces engine performance, and can eventually cause stalling. In rare cases, if sediment bypasses the filter, it can reach the injectors and damage them as well.
Air in the Fuel System
When the tank runs completely dry, air gets pulled into the fuel lines. Restarting the vehicle afterward often requires several attempts, as air pockets disrupt the smooth flow of fuel to the engine.
In some cases, running dry can cause the fuel system to lose prime, meaning the pump must work harder to restore normal pressure. This added strain increases wear on the pump and can shorten its overall lifespan.
Damage to the Catalytic Converter
If the engine stalls repeatedly while running out of gas, unburned fuel may enter the exhaust system. This can overheat the catalytic converter, causing internal damage over time. Since catalytic converters are expensive to replace, preventing this problem by avoiding low-fuel driving is far more cost-effective.
Other Risks of Driving on Empty
Running out of gas can also create safety concerns. If your vehicle stalls in heavy traffic or on a busy highway, it puts you and your passengers at risk. Even if you manage to pull over safely, refueling from an empty tank can leave you stranded for longer than expected, especially if air needs to be purged from the system before the car will start again.
How to Protect Your Fuel System
The best way to avoid fuel-related damage is simple: keep your tank at least one-quarter full whenever possible. This helps ensure:
- The fuel pump stays properly cooled and lubricated
- Sediment at the bottom of the tank isn’t constantly stirred up
- Air stays out of the fuel lines, maintaining smooth pressure
- The catalytic converter avoids exposure to unburned fuel
If you’ve accidentally run your tank dry, having the fuel system inspected can prevent hidden problems from developing later. Our technicians check for restricted filters, weak fuel pumps, and other issues that might affect long-term reliability.
Keep Your Vehicle Reliable With Morrison Tire Inc.
At Morrison Tire Inc. in Garden Grove, CA, our technicians inspect and service your fuel system to keep it operating at peak efficiency. Whether you’ve run out of gas recently or want to make sure your pump, filter, and injectors are in great shape, we provide thorough diagnostics and expert maintenance.
Schedule an appointment today to protect your vehicle and keep it performing reliably mile after mile.