Symptoms of a Bad Fuel Pump Relay & Replacement Cost

If you are looking to find out symptoms for a bad fuel pump relay, there are a few things that need to be considered first. For starters, you need to know where is the fuel pump located and how it functions.

Then you can find out the symptoms and understand them. It is also useful to know whether it needs to be replaced or not. Continue reading to find out all information about a bad fuel pump relay.

a bad fuel pump relay
a bad fuel pump relay

What is a fuel pump?

It is an electronic component that is found on all vehicles comprising an internal combustion engine. It works as a primary electronic switch that controls all power to control the pump and is often found in the fuse box of the engine located at its bay.

Mostly it is controlled by two components of the engine, which are the ignition and powertrain control module. To function it needs current flow so when the ignition is switched on the function takes place.

What causes a bad fuel pump relay?

Typically, the relays have a winding when the voltage is applied it pulls itself in a set of contacts which pass higher voltage, and it can cause the contacts to burn. If the contacts are burned, then they will cause higher current draw and get fried.

This will cause the connection to break, and the relay dies out. You will need to replace it as soon as possible and find out the exact symptom and cause. For this, you need the following guidance:

Symptoms of a bad fuel pump relay

The relay can break down due to a number of reasons, and almost anything can affect the life of a fuel pump relay.

symptoms for a bad fuel pump relay
symptoms for a bad fuel pump relay

The performance and vital function of a fuel pump relay is the most important aspect for the fuel engine, and if it goes bad, then malfunction of the engine takes place. The significant signs and symptoms that cause fuel pump relay failure are:

Engine stalling

As soon as you switch on the ignition, the relay starts working to maintain the voltage to start the fuel supply.

If the relay’s function fails, you are unable to start the engine, and it starts stalling. It can be related to a human body; if it doesn’t have the energy, it cannot function.

This is how an engine works as it needs proper fuel intake to function to drive. To fix this issue, you need to replace the whole fuel pump relay by a mechanic or a proper car professional.

It is also possible that a moderately bad relay still lets the car to start after a while, but if it has totally died down, then you have to replace it.

Non-starting engine

The second symptom of a bad fuel pump relay is an engine not starting at all. The fuel pump has an obligation to work efficiently in order to maintain the engine’s lifespan.

If an engine doesn’t start, it means that the fuel pump relay is in replacement mode. Mostly when the fuel coming in the combustion chamber is not up to the mark and has low pressure, these are the symptoms of a bad fuel pump relay, and the engine starts to decline due to this issue.

Power loss

When you feel that your engine is starting to shut down and is losing its power to function while you are driving.

Then it means that your fuel pump relay is in bad condition. Your car will cease to move, and the issue will go worse if the fuel pump relay is nor replaced or fixed.

The fuel pressure and filter need to be checked before replacing the relay, so you know for sure that this is the exact symptom.

your fuel pump relay
your fuel pump relay

Non-responsive fuel pump

There are times when a fuel pump is not giving any response, not even a single sound. It behaves is similar when the water pump is damage. Improper deliverance of current flow can cause the fuel pump to perform its respective functions.

You have to make sure that if you are starting the car and it is not giving its signally sound then there is something wrong with the fuel pump relay. This can lead you to try switching on the ignition again and again, and the answer will still be the same that the fuel pump relay has died down.

If you are experiencing this sign with your vehicle, then it is time to see a car professional and get a proper inspection of your whole engine and transmission system.

Diagnosis of a bad fuel pump relay

Here is a guide to diagnosing a bad fuel pump relay in your vehicle if you want to discover it yourself and not see the mechanic at the moment:

Try locating the fuse box using your car manual.

There you will locate the fuel pump relay.

You will have to set the multimeter system on the ohms scale.

With the help of a 12V battery or any voltage regulator, you will test the fuel pump relay.

The relay now needs to be connected to the base of the power supply using a ground pin.

If the meter is showing continuity, then you have a moderately working fuel pump relay but if there is no continuity present then sadly the fuel pump has died down and has failed.

How to replace a bad fuel pump relay?

If you are looking for steps regarding the removal or replacement of a bad fuel pump relay, then you need to prepare yourself for the process first.

Arrange all the tools and supplies needed for the job and start working with no time to spare!

Any car owner should be efficient enough while getting the tools, as they need to be of good quality, so the process of replacement is insured properly. The following tools are essential to gather as soon as possible:

  • Pack of wrenches
  • Needle nose pliers
  • Wheel chocks
  • Standard socket racket

The rest of the tools are present in almost every car repair kit.

Steps of How to replace a bad fuel pump relay

  1. First of all, gather all the tools mentioned above at one place and prepare your car in a shady area for the assessment and the replacement procedure.
  2. The inspection will take place where the fuse box is located. Find out where it is located using your vehicle’s respective manual.
  3. When you have finally located the fuse box, there will be no worries left in identifying the fuel pump relay. Mostly anyone can identify it by referring it to the diagram on the fuse box.
  4. The next step is to turn on the ignition; this is where the main part starts taking place.
  5. You have to carefully listen to the relay in order to see if there is any buzzing signaling sound coming out of the engine.
  6. Furthermore, start the engine of your vehicle.
  7. Check your engine and fuel filter for any oil pressure.
  8. You have to follow all these steps while your car is parked horizontally on a flat surface.
  9. Now utilizing the wheel chocks. Carefully put them around the tires of your vehicle.
  10. In the place of the smoking lighter place in your vehicle place, a 9V battery saver carefully.
  11. Now is the time to disconnect the battery from the vehicle, and then you need to remove the fuel pump relay. For the removal of the fuel pump relay, make sure all tools are present in your tool kit.

Your car manual will guide you on how to remove it because every vehicle has a different step to it. Make sure to remember all steps of removal.

  1. Get yourself a new fuel pump relay and match it with the old one in order to understand if you got the right one or not. Installation of the new fuel pump relay should take place now in the right location.
  2. Carefully cover the fuse box. To ensure that the fuel pump relay has been properly sealed you have to remove and replace the fuel cap from the fuel tank.
  3. The battery that you disconnected earlier needs to be fixed back into the hood under the vehicle.
  4. The clamps on the battery tunnels should be properly tightened and rechecked for assurance and safety precautions.

Now is the time to have a test drive in order to ensure that the procedure went well and check if the engine light is still on or not.

Fuel pump circuit breaker reset

There are several times when there is no fuse box in a car, and a circuit breaker is present in the fuel pump relay instead. If you are unable to find the fuse, then it is time you check your car manual for the fuel pump cut off circuit breaker’s location.

Fuel pump circuit breaker
Fuel pump circuit breaker

Usually, they have a button on top that pops up when it trips. You will need to push this button back until it makes a clicking sound. Then you will carry out a fuel pump testing.

If you see that the fuse is good and the circuit breaker has not been tripped, then it means that the engine is not getting access to fuel pressure.

On this point, the car professional has to open the rubber boot at the throttle body and then spray a tiny amount of starter fluid insider the manifold.

Then reinstall the boot and try switching on the ignition. In cases of a bad fuel pump relay, the engine will halt right after switching on for a few seconds.

This will optimally verify that if there were any access of fuel to the engine, it would have functioned correctly, resulting in no fuel pressure at the same time. The electric fuel pumps on the fuel injection systems are controlled electronically, and they always need to produce high pressure to give an allowance to the injectors of producing atomized fuel.

This sufficient amount of spray is taken into the direct injection system. The fuel pressure has to be 35-45psi range.

This will enable you to see the fuel pump’s circuit breaker in immense detail so if there is nothing wrong with the fuse and still the fuel pump relay is bad then there might be an issue with the circuit breaker.

Careless mistakes regarding a fuel pump relay

The electric fuel runs merely with your engine by delivering high pressure of fuel to the injectors.

The fuel pump only keeps its cool temperature by staying submerged in the fuel. If you let your tank running empty before filling it up, then the fuel pump relay will die out before its designed lifespan.

When you shut off the engine at a low fuel level, it can drain out from the priming chamber into the fuel delivery system.

When you start on the ignition, the pump will run hot and unprimed, causing to burn out the pump motor immensely. This is why a fuel pump relay shuts out when you try to refill the tank with gas. You have to avoid restarting it while it’s hot as well.

Another common mistake that many car owners make is that they let the car stand in their front porch while it heats up under the sun causing the engine to burn.

This will obviously make it hard for the car to start up and cool its fuel down. This regular heat up will cause the fuel pump relay to backfire.

Read: What Fuel Should I Use In My f-150 Ecoboost

Bad Fuel Pump Relay Replacement costs

The costs of the replacement of a bad fuel pump relay vary from vehicle to vehicle. But the average cost ranges from 95-140$.

These costs are divided into many categories, such as the expenses of the tools you need to arrange and the parts for the vehicle.

As well as labor costs that you avail from a car professional if you do not do it on your own. The fuel pump relay can be bought over online and at any hardware store as well. 20-50$ are the costs for the parts alone.

The rest of it is the labor cost. You will have to get yourself a good and high-quality fuel pump relay, so it doesn’t budge for a long time.

high-quality fuel pump relay
high-quality fuel pump relay

One time investment is really good if you don’t want long term issues and expenses trying to fix them. If you don’t want to spend your savings over the costs of further repairs that a low-quality fuel pump relay has caused then don’t hesitate in nurturing your car’s wellbeing.

The hourly rate of labor cost can affect the overall expense of this replacement procedure. If your car professional is charging you at an affordable rate per hour, then you can go home carefree with your fuel pump relay replaced, as it only takes an hour to get fixed. The new fuel pump relay is not that expensive so that you can be assured about replacement costs.

Tips of care

Here are some tips regarding the maintenance of your new replaced fuel pump relay:

  • Don’t let your fuel level drop an eighth of the tank.
  • Keep the pump motor cool.
  • Don’t let the pump motor lose its prime.
  • Don’t use all the fuel up at once; try maintaining it for two days at least.
  • Keep your car inspected at all times, especially the engine and fuse box.
  • Check your fuel filter and pressure at all times. Even if there is no issue faced yet, still you will need weekly inspections.
  • Never hesitate to replace the fuel pump relay as you will regret later if you don’t do it in time.
  • Always get your tank filled with good quality gas. Contaminated gas can cause the engine to halt and not start at all.
  • After an accident or a bumpy ride, you can experience fuel shut off. The fuel shut off switches can be tripped by a severe jolt so press it to reset.
  • Don’t forget to take a test drive right after the replacement of the fuel pump relay as it is important that you do it on your free day.

If you start your car the next day while you are getting late for work and somehow the procedure didn’t work, then you will face two issues at the same time.

Final thoughts

This context is your ultimate guide to all the information you need to know about fuel pump relays/bad fuel pump relays. The main focus is on symptoms of a bad fuel pump relay and the replacement of it.

The costs and categories have been explained with all the details. If even after the replacement of fuel pump relay your issue hasn’t been solved you can take your car to a professional for another checkup of the whole interior parts.

The maintenance of your car’s wellbeing is the most important aspect of a person’s life. If the car is not functioning properly, which it obviously can’t at all without a proper fuel pump relay, then you need to replace it as soon as possible without any delay.

We will be happy to hear your thoughts

Leave a reply

Automotive News, Guide & Advice | AutosGuide