Everything to Know About Fuel Pumps

Someone interested in high-performance aftermarket car parts might already know a fair amount about fuel pumps, including specialized options like the Walbro 255lph fuel pump.

If you’re not a car aficionado and you don’t have experience in aftermarket parts, in particular, that may sound like a foreign language to you. 

As a car owner, and particularly if you’re thinking about buying a used car and you want to make sure it’s going to be in good shape, it’s advisable to learn about some of the different components of a car. 

One important one is the fuel pump, and the following are critical but also general things to know about fuel pumps. 

If you do decide that customizing cars is in your future, it’s also important to have this foundational knowledge. 

The Basics

A fuel pump brings fuel from your gas tank to your engine. Fuel pumps may be powered electrically, and they’re either in the fuel tank itself or on it. 

A fuel pump is responsible for supplying fuel at a consistent pressure, so your engine runs smoothly. 

As was touched on, many fuel pumps are electronic. This means they’re usually inside the fuel tank, and they use electromagnetic motors to force fuel at a high pressure into the engine. Electronic pumps are typically used along with fuel injection systems. 

A mechanical pump operates from the engine’s motion. These are mounted outside the fuel tank, and as a diaphragm expands and contracts a low-pressure system is created. This then forces fuel into the engine from the tank. 

If you have a mechanical fuel pump and there’s an issue, it may be easier to deal with because there are fewer moving parts. 

Electronic pumps not only have more moving parts, but they also have complex electronic control systems. 

So what could indicate a fuel pump is failing? Even though the reasons a mechanical versus electronic pump fails may be different, the results can be the same. 

Sputtering At High Speeds

If your engine starts to appear as if it’s sputtering at high speeds, it could be an indicator that your fuel pump is failing. 

What might happen at consistently high speeds is that your vehicle will start to sputter suddenly, then will go back to normal. 

The reason this is a warning sign of a fuel pump problem is that the pump is having problems supplying fuel consistently to the engine at the right pressure level. 

When this first becomes a problem, the sputtering might only go on for a minute and sometimes, this is confused for dirty gas. 

Increasing Temperature

If your car temperature is rising, it may mean that not only is a fuel pump issue occurring, but it could be an emergency. Look at the temperature of your car, and if the heat goes up and then the car stalls, the fuel pump may be the cause. 

If your car continues stalling out, you likely need to replace your fuel pump.

Power Loss During Acceleration

If you’re trying to accelerate after stopping and your car loses power, then your fuel pump may be the problem here as well. 

There’s a reason for this. When you accelerate your vehicle, it means it needs more fuel. That’s putting more strain on the fuel pump to work harder. If a pump isn’t working properly, then it might not be able to keep up with that demand, then your engine isn’t getting enough fuel as you’re trying to accelerate. 

There’s also something that can happen where you’re driving at a normal and consistent speed. Then, all of a sudden, it might feel like your car is trying to surge like you’ve pressed the gas pedal. Check the fuel pump if you experience this. 

There are different reasons a fuel pump might experience issues, including rust on steel tanks, and plastic tanks can start to break down over time. 

What If You Need to Replace a Fuel Pump?

If you determine that the cause of your vehicle issues is because of your fuel pump, the replacement pump varies depending on the make and model of the vehicle and in some instances the size of the engine as well. 

If you have a high-mileage older vehicle with a fuel pump issue, you’ll probably need to replace not only the fuel pump but the sending unit because it’s easier. Otherwise, you might just replace the pump. 

If you have questions about your fuel pump and you aren’t sure what to look for, speak with a professional.