10 Signs Of A Bad Fuel Pump – How Do You Know If The Fuel Pump Is Bad? 

The fuel pump is responsible for providing the required amount of fuel to the engine's cylinders to ensure proper functioning. Over time of use, and like any other vehicle's components, your fuel pump might wear or tear, resulting in significant issues with the vehicle.

In this article, we will walk you through the different signs of a bad fuel pump that you must keep an eye on. If you see any of these signs, you must not ignore them, and you have to take your vehicle to the repair shop immediately. 

What is the fuel pump, and what is it used for? 

 

The fuel pump is the part of your vehicle that is responsible for pushing and supplying the engine with the required amount of fuel at constant pressure, so your engine runs smoothly. 

There are two types of pumps: the mechanical pumps and the electronic pumps. Mechanical pumps usually exist in older vehicles, while electronic pumps exist in newer vehicles.

 

• Mechanical pumps 

 

 

You will find this type of pump, mostly in older vehicles. The mechanical fuel pump runs using the energy produced by the engine motion. This type of pump has a diaphragm sticking outside of your fuel tank and supplies the engine with fuel at low pressure. 

The mechanical pumps consist of few moving parts; most problems with this type of pumps occur at the diaphragm. In general, mechanical pump problems are easy to diagnose and fix. 

 

• Electronic pumps 

 

 

You will find electronic pumps in newer vehicles as they are made of complex components. The electronic pump is placed inside the fuel tank a supplies fuel to the engine at a high pressure using an electromagnetic motor. 

Due to the complexity of the electronic pumps, problems with this type of pumps are hard to diagnose and, therefore, hard to be fixed. This is because the electronic pumps consist of many internal moving parts, and any of these parts could malfunction, making it hard to pinpoint the error.

10 signs of a bad fuel pump  

 

Although the mechanical and electrical pumps can be completely different, problems with both pumps have almost the same signs. Therefore, if you come across any of the signs that we will be listing below, you must get your pump replaced immediately despite your pump type. 

 

• When driving at high speeds, the engine might start sputtering 

 

 

One of the first signs for a bad fuel pump occurs when constantly driving at high speeds. If you noticed that your engine starts sputtering when driving at high speeds, this indicates a clear issue with your fuel pump. Engine sputtering happens as the fuel pump is not able to maintain the constant stream of fuel supply at the required constant pressure. 

 

• Significant increase in vehicles temperature followed by car stalling  

 

 

Another important sign indicating an issue with your fuel pump is a rise in temperature. If you notice that your temperature gauge is showing a continuous increase in the vehicle temperature followed by vehicle stalling, you must get your fuel pump diagnosed and repaired immediately.

It is important to note that the rise in your vehicle's temperature could be due to multiple issues that are usually very significant. Therefore, even if you are not sure that it's your fuel pump, you must take your vehicle to the nearest repair shop and get it fixed immediately. 

 

• Problems with the fuel pressure gauge 

 

 

The pressure gauge indicates how much fuel is being supplied to your engine. Every vehicle has a specified amount of fuel that must be supplied to the engine continuously so it can function properly. 

If this amount of fuel was not supplied to the engine, you might start having problems that could lead to significant failures.

The best place to start with is your vehicle's owners manual; In this manual, it will tell you how much fuel should be supplied to your engine at any time. So what you can do is to have someone revive the vehicle while you check the pressure gauge. If the fuel pressure gauge shows that less fuel than what's required, you must get your fuel pump fixed immediately. 

 

• Your vehicle might lose power when it's under stress 

 

 

If you're coming back from a grocery trip or using your vehicle to haul heavy cargo while moving, this is considered a stressful situation for the vehicle. In stressful situations, additional stress is put on the weak parts of your fuel pump, challenging it from providing the required fuel supply to the engine. 

 

• Sudden surge while driving at normal speeds 

 

 

Faulty parts within your fuel pump can cause the vehicles to surge suddenly without any previous warning signs. This sudden surge occurs as the fuel pump motor is trying to resist the continuous demand for fuel supply by the engine. 

 

• The sudden decrease in gas mileage 

 

 

In your fuel pump, there is a relief valve that is used to control how much fuel goes into your engine. If this will relief valve does not open at the right time, more fuel will be supplied to the engine than needed. As a result, you will start noticing that your vehicle fuel tank needs to be refilled more often due to low mileage issues. 

 

• Your vehicle might not be able to start 

 

 

In difficult situations with a fuel pump, you might get to a point where you can't start your engine. When the fuel pump is not doing its job, no fuel will be supplied to the engine, and therefore, the engine will not start. While the engine might crank and rev, it will never start.

The first thing you need to do when diagnosing your fuel pump is to look for low pressure in the fuel pipes or a blown a fuse.

 

• Hearing weird whining noise coming from the fuel tank 

 

 

As a rule of thumb, hearing any weird noises coming from your vehicle is a very bad sign, and you must take action immediately. This is because these weird noises can be related to significant problems that could lead to complete engine failure or vehicle damage.

Like any weird sound coming from any part of your vehicle, if you hear a whining sound coming from your fuel tank, this is an indication of an issue with the fuel pump.

During normal operations, your fuel tank pump would make some humming sound; however, if this sound starts to get louder and louder and more like a whining sound, this is an indication of either a contaminated fuel, damaged fuel pump, or not enough fuel inside the fuel tank. 

 

• The vehicle has a hard time starting  

 

 

While we mentioned before that that fuel pump could lead to the vehicle not starting, a bad fuel pump might give the vehicle a hard time to start, but start at the end.

As we mentioned earlier, the fuel pump provides the engine with the required fuel continuously right after turning on the ignition. A weak fuel pump might cause the vehicle to take a couple of cranks so it can start. In difficult situations, you might need to turn the key multiple times before the vehicle starts. 

 

• Engine overheating 

 

 

When the fuel pump does not provide the required amount of fuel to the engine, the engine stresses and, therefore, overheats. Engine overheating is one of the most significant engine problems that could result in a quick engine failure. 

 

Is it worth replacing the fuel pump? 

 

This question depends on many different factors. To best help you, you need to ask yourself a couple of questions, so you can make an informed decision about whether to fix your fuel pump or not:

• Is the fuel pump issue the only problem your vehicle is suffering from?
• Does your car have high mileage?
• Are they required repair costs getting close to the worth of your vehicle or higher? 

If any of your answers to the previous questions is a yes, then you might consider selling your vehicle as junk because it's not worth replacing or fixing it. 

Luckily, cash car buyers Are here to assist you! At cash car buyers, we buy any vehicle despite its condition. We buy wrecked, broken, or completely damaged vehicles. Furthermore, we offer the highest prices among all competitors within the area. Besides, we don't only buy your vehicle with the highest prices, but also we provide free towing for all customers despite their living location.

All you need to do is to give us a call, listen to or instant offers, accepted, get your vehicle involved within one to three days, and finally, receive your cash payments right on the spot! 

 

FAQ about signs of a bad fuel pump 

 

 

• Will a bad fuel pump through a code? 

 

 

While a faulty fuel pump will not directly result in a check engine light come on, the impact of this faulty pump on the engine causes the check engine light to illuminate.

For example, if the faulty fuel pump caused the engine to overheat, the check engine light will illuminate the tool, warn you that your engine is overheating. Similarly, if the files, if you'll pump resulted in the vehicle not to start, the check engine light might illuminate, indicating issues with the starter. 

 

• How do you check the fuel pump? 

 

 

There are several steps you can take to check for issues with your fuel pump. Some of these steps include doing an electrical test on the fuel pump fuse and the pump voltage itself. If this did not detect the problem, you might need to do a fuel pressure test using a pressure gauge. 

 

• How expensive is it to replace a fuel pump? 

 

 

In general, expect to pay between $400 and $600 to replace the fuel pump. This repair cost includes the parts itself and the labor cost. While the drive can do many mechanical repairs, replacing the fuel pump is one of the repairs that must be performed by a skilled mechanic. 

Even if you know how to replace the fuel pump, it is recommended that you get it replaced VI, a professional mechanic.

It is important to fully understand that mechanical repairs costs are divided into two components: parts costs and labor costs. Therefore, be very smart when choosing where to go and replace your fuel pump. This is because replacing the fuel pump at a dealership costs much higher than replacing it at a small repair shop. 

While you can save a lot of money by repairing your vehicle at a small mechanic shop, some luxury vehicles are recommended to be repaired at the original manufacturer to avoid any mistakes that could result in more complicated problems. 

 

• How long do fuel pumps last?

 

 

Fuel pumps do not go bad before 200,000 miles in most cases. However, experts mentioned that drivers should expect fuel system problems at around 100,000 miles. Of course, this is a rough estimate and the actual lifetime of the fuel pump depends on your vehicle, driving style, and the environment. For example, if you live in an area that has a lot of uphill type of roads come up will be challenging the engine and the fuel pump to perform in these stressful environments.

 

• What causes a fuel pump to go out?

 

 

Some many reasons and factors could reduce the lifetime of your fuel pump, including contaminated fuel, vehicle overheating, issues with the fuel pump gears, and others.

Surprising that debris, make their ways to the fuel pump and clogging it, resulting in fuel pump failure. Therefore, whenever you open your gas tank, make sure that you close it right away to avoid any contamination from getting to your tank and, therefore, to your fuel pump.  

Another factor that could result in damage if your fuel pump is running at a low fuel level. This is because the fuel pump would send some of the fuel to the engine and bring it back to cool down the fuel tank. However, if you're running on a low fuel level, you will result in overheating the fuel inside the fuel tank, which would, therefore, damage your fuel pump.