What causes a fuel pump to fail? (4 common reasons)
The fuel pump draws gasoline from the fuel tank and sends it to your engine. A good fuel pump maintains constant pressure so you always have enough fuel no matter how hard you press the accelerator. Over time, fuel pumps can fail for a variety of reasons. Did you know there are some things you can do as a driver to cause premature fuel pump failure?
With proper fuel system care and good quality fuel, your fuel pump should last at least 100,000 miles, and possibly several times that. There are usually no scheduled maintenance intervals, but you can always check your user manual. Here are some common causes of fuel pump failure:
1) Age-Related Degradation (keep an old car)
Even with the best care, most parts will eventually wear out and break. This is not an inherent defect on your or the manufacturer’s part. Most components are built for a specific service life.
2) Bad or Incorrect Fuel (Signs of Bad Gasoline)
Contaminated fuel is a leading cause of premature fuel pump failure. If the fuel filter is not serviced as frequently as it should, dirt and debris can get into the fuel pump itself. This causes further wear on the fuel pump. Either the fuel pump has to work harder to overcome the resistance of the deposits or the deposits damage the pump itself.
Not all fuels are created equal. In addition to choosing the right octane rating for your gasoline, it’s a good idea to choose a good gas station to maximize your chances of getting quality fuel. Any gas station can be stocked with bad fuel, but some stations are more likely than others.
Contaminants or water in the fuel can clog fuel filters, putting extra strain on the fuel pump. Be mindful of additives in your tank as well. Only use known fuel system additives recommended by your mechanic. Using the wrong type of fuel can quickly cause fuel pump problems. Never put diesel in a gasoline vehicle or vice versa. This is a good way to destroy the fuel system and possibly the engine.
Using ethanol in a vehicle not designed for ethanol can cause fuel pump problems, depending on the concentration. Most modern fuels contain low concentrations of ethanol (around 10%). E10 gasoline is compatible with most modern gasoline fuel systems.
3) Running on an empty tank (high fuel consumption)
It is important to operate your vehicle with the tank at least 25% full to properly cool the fuel pump. Frequently driving with the tank less than a quarter full risks damaging the fuel pump from overheating and may cause premature failure.
The fuel pump is submerged in fuel and uses that fuel to cool the unit. Low fuel levels will increase the temperature of the fuel in the tank and fuel pump. Extra heat means extra wear and tear.
Low fuel levels also increase the chances of sucking in debris from the bottom of the tank. This can cause the fuel filter to prematurely saturate with debris or allow debris to get into the fuel pump itself.
4) Clogged Fuel Filter
The fuel filter has an important job: filtering out deposits and contaminants, such as dirt and rust particles, that can build up inside the fuel pump. When these contaminants build up, the fuel strainer becomes clogged and the pump can no longer suck in enough fuel to function properly, which can lead to fuel pump failure. When your fuel pump fails, you’re likely left stranded. Fuel pumps can fail intermittently or fail completely, preventing you from driving your vehicle at all. Intermittent fuel pump failure is similar to an engine stalling and can get worse over time.
Symptoms of a Failed Fuel Pump
Diagnosing a failed fuel pump is usually relatively easy. There are a few things you can check to speed up the process.
1) Listen for a buzzing sound
When you turn the key for the first time (or open the door on some models), you’ll hear a slight buzzing sound. This is the fuel pump that supplies fuel to the fuel system. Some fuel pumps are very quiet and you may not hear it. If you’ve always heard a buzzing or humming noise, but one day you no longer hear it, your fuel pump may be faulty.
2) Check the fuel pressure
There should be fuel pressure when you start the engine. You can run a fuel pressure test when starting the engine to make sure there is fuel pressure. If there is no fuel pressure, there is a good chance that there is a problem with the fuel pump.
3) Check the fuses and relays
To avoid unnecessary fuel pump replacement, make sure all fuses and relays are good. It is especially important to check the fuel pump fuse and relay. A bad fuse or relay will cause the same symptoms as if the fuel pump had stopped working altogether.
Preventing Fuel Pump Troubles (Regular Maintenance)
Regular vehicle maintenance is important to avoid fuel pump failure. Fuel-related areas to consider include:
– Change the fuel filter at the manufacturer’s recommended intervals to prevent filter clogging by rust, dirt, and other contaminants.
– Check the filter socket. The filter socket is often located at the bottom of the fuel pump. Replace the filter element if it is dirty or damaged.
– Be aware that rust in the fuel tank can also cause problems.
– Have a professional check your fuel lines for signs of damage such as cracks or leaks that could allow moisture and contaminants into the fuel system.
Fuel Properly
To extend the life of your fuel pump, follow these tips when refueling:
– Always keep your fuel tank at least a quarter full. Low fuel levels can cause the fuel pump to overheat and shorten its lifespan. – Use gas stations that use premium fuels to minimize the chance of using low-quality gasoline or gasoline that contains excessive water.
– If you have problems with moisture or condensation in the tank, consider using a fuel additive to absorb and remove water from the system.
Good Fuel Filtration
– Invest in a quality fuel filter to protect your fuel pump and engine from a variety of contaminants.
– Check and change your fuel filter according to the manufacturer’s recommendations to avoid clogs and other problems.
– Check fuel lines and other fuel system components regularly for signs of wear or contamination. Conclusion
Fuel pump failure is not that common, but it can and is more likely to occur in vehicles that are driven frequently with tanks less than a quarter full. To avoid fuel pump problems, be sure to use clean gasoline, change fuel filters regularly, and keep fuel levels at or above a quarter of tank capacity.
