Fuel Pump Not Priming – What’s The Likely Cause and Fix?

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A fuel pump that isn’t priming can lead to a potentially dangerous situation. If the engine isn’t getting the fuel it needs, it can overheat and cause severe damage.

If you’re not sure whether your fuel pump is priming, here are a few signs that might indicate the problem: the pump is making a high-pitched noise, the fuel line has water or foam on it, or there’s a strong smell of gasoline.

If you notice any of these signs, it’s important to take action if your fuel pump not priming and have your fuel pump checked.

How To Prime Fuel Pump

How To Prime Fuel Pump

If you are trying to prime a fuel pump, here is what you should do:

1. Before starting the engine, make sure that the gasoline tank is full. Also, it is best if there is enough gas in the tank to prime at least one fuel pump or two.

2. Turn on the ignition and keep it on until all of the pressure has built up in the fuel lines (the gauge will rise). You may have to wait between five and ten minutes for this process to complete.

3. Once pressure has built up, turn off your ignition and let the pressure drop back down into normal operating range before attempting to start your vehicle again with any amount of gasoline left in the tank. 

4. Prime all four sides of each fuel line at once if possible; this will help ensure that each side receives equal treatment from your priming equipment so that no side of a fuel line can be damaged by excessive flow rates from a single point on its length during priming operations.

5. Some pumps can be primed only by applying small amounts of primer fluid through their filter screens into their filters or directly into their manifolds (where they connect with other components).

Priming A Mechanical Fuel Pump

Priming A Mechanical Fuel Pump

To prime a mechanical fuel pump, you need to have the following things:

  • Fuel injection pump
  • Electrical connections

One of the first things you will want to do is find out what type of fuel injection pump you have. There are two types of pumps: direct drive and those that use belts.

In either case, make sure that your fuel pressure regulator is set at about 30 PSI.

After connecting all your lines, it’s time to test them for leaks using a fluid leak detector like this one from K & N.

If everything looks good after testing your lines, then it’s time to prime the system with a clean-burning gasoline additive like this one from Motul.

If your car has an automatic transmission, add 2 ounces (60 ml) of ATF+4 Automatic Transmission Fluid Plus per quart (1 liter) of engine oil when adding gas or diesel fuel.

Now it’s time to hook up the electrical connections so that you can prime your mechanical fuel pump in 5 minutes or less.

Fuel Pump Not Working Symptoms

Fuel Pump Not Working Symptoms

There are several symptoms of the fuel pump not working. Some of them include:

1. The fuel pump stops working suddenly. This can be caused by several factors like the low pressure in the system, a clogged filter, or a bad electrical connection.

If you have recently changed your fuel filter and it is still not working, then it might be time to get your car checked out by a mechanic

2. When you turn on the ignition key, nothing happens (check engine light is on). This could be caused by any one of these issues: 

  • Low fuel pressure may indicate a problem with the system itself. You should consider this because this will increase the cost of repairing your vehicle if left untreated. 
  • Fuel Filter that needs to be replaced 
  • Bad wiring 
  • Faulty computer 
  • Timing belt tensioner

3. Sometimes when you start up your car, no spark appears at all and then after about 10 seconds an orange glow appears, and after another few seconds an engine starts up but doesn’t sound right, so you need to drive around with the radio turned off until things settle down again.

New Fuel Pump Not Priming

New Fuel Pump Not Priming

A new fuel pump may not be priming because of one of the following reasons:

First, check to see if the primer valve on the fuel pump is open. It is located under the float bowl and may have a spring-loaded plunger that needs to be pulled back before it can prime.

Second, if you have a multistage fuel system or high-pressure injection pumps, the injectors may need to fire up before the pump primes. This can be tested by using an ohmmeter across each injector’s electrical connection.

Each time you turn on your ignition and then run your engine for at least 30 seconds, measure resistance between each injector’s electrical connection with an ohmmeter (not as suggested in some manuals). 

A high reading indicates no spark from any of them; a low reading indicates they are all firing properly, but any of they is generating not enough voltage to force fuel into the tank through their respective filler necks.

The average reading should be around 1 megaohm (ohm = milliohm = thousandth of a mho), with most likely readings being between 0 and 10 megaohms.

If this test reveals all are working properly, but not enough voltage is present at any point in time, check out Fuse number 7 – which supplies power to your electronic throttle control unit (ECT).

If this fuse is blown or open circuit, it could be causing problems with your ECT and/or computerized throttle control module (CCM).

Mechanical Fuel Pump Loses Prime

Mechanical Fuel Pump Loses Prime

The prime or the priming is very important when you have a mechanical fuel pump. If it loses prime, it will not be able to start the engine, which can lead to accidents in your car or truck.

This happens because there are some types of fuel pumps that need priming every time before they can start working.

The most common fuel pump that needs priming is a pressure-based system that uses air pressure to work.

Other types of fuel pumps do not require any priming, but they use electric power as their prime source instead.

When you lose prime on an electric-powered fuel pump, then the motor will still turn, but it won’t produce any power, and it will not move the piston forward either, so no movement occurs in your car’s engine when this happens.

Priming A New Fuel Pump

Priming a new fuel pump is easy to do. There are two different ways to prime a new fuel pump:

  • The first way is to fill the tank with regular unleaded gasoline and allow it to sit for approximately 30 minutes, then drain the gasoline out of the tank and repeat this process twice more before filling the tank with premium unleaded gasoline.
  • The second way is to fill the tank with premium unleaded gasoline, start your vehicle and let it run until it reaches operating temperature (check engine light will come on). After that, you can switch off your engine and let it sit for about 20 minutes before switching back on again.

This should prime your new fuel pump enough so that you can run your vehicle safely without any problems in the future.

What Is Fuel Pump Relay?

What Is Fuel Pump Relay?

A fuel pump relay is a device that controls the flow of fuel to the engine. It is an automotive fuse-like electrical device.

It contains an electric motor, a solenoid, and some other parts. When the solenoid receives power from the battery, it turns on and starts rotating with the help of an electromagnet.

This, in turn, opens up a valve that allows gas to enter the engine. 

If there is no power present, it will automatically close down again.

The purpose of this relay is to make sure that your car gets enough fuel even if you have not driven for some time, as well as if you are driving through water or mud where your car can’t move because of any obstruction in its paths like debris or potholes, etc.

Common Problems After Changing Fuel Pump

Common Problems After Changing Fuel Pump

Some common problems occur after changing the fuel pump. Some of them are as follows:

  • Fuel gauge does not work correctly, in which case it may take a while to get used to the new fuel level, and then it is advisable to drive with caution because there is no way you can tell how much fuel you have left until you fill up again. 
  • The car will not start or stall when starting, in which case one needs to check for any technical issues such as low voltage or battery voltage or even a broken wire harness on the engine bay. If this happens, there could also be an issue with a faulty fuel pump. 
  • After driving for about two days without refueling (which isn’t recommended), the check engine light comes on, indicating that there might be an issue with your catalytic converter; in this case, you need to contact your mechanic, and they will let you know what needs fixing.

Mini Cooper Fuel Pump Reset

Mini Cooper Fuel Pump Reset

The MINI Cooper has an inertia button that may be utilized to restart the fuel pump in the event of a rollover or other unintentional triggering. It is placed within the compartment of the engine on the driver’s side of the car.

Here are the steps to reset the Mini Cooper Fuel Pump:

1. First, you need to turn off the ignition key switch and disconnect the battery from the negative terminal.

2. Next, remove the fuse from the fuel pump connector and then loosen fuel cap screws by turning counterclockwise with a pair of needle-nose pliers.

3. Finally, start the engine on a flat surface while applying firm pressure on the brake pedal until it stops completely (about 5 seconds). Then disconnect the negative battery cable and wait for 3 minutes before reconnecting it back to its positive terminal.

Mini Cooper Fuel Pump Problems

Mini Cooper Fuel Pump Problems

Mini Cooper Fuel Pump Problems are related to the fuel pump and its electrical system.

There are many Mini Cooper Fuel Pump Problems, but the most common ones include low fuel levels, noise, and poor performance. If you are experiencing one or more of these problems, a solution is likely available.

To diagnose the issue, start by checking the fuel gauge. If it is low or reading incorrectly, this may indicate a faulty fuel pump. If the pump is not the issue, you may need to check for fuel leaks.

Ensure all the gas cap screws are tight and check for any dents or damage to the fuel tank. If all of these measures fail to solve the issue, likely, the engine is not receiving enough fuel. In this case, you may need to replace the fuel pump.

Fuel Pump Not Priming Civic

If you are having trouble priming your fuel pump on your Civic, there may be a few troubleshooting steps that you can take. 

  • First, make sure that the pump is securely fastened to the car. 
  • Second, make sure that the fuel lines are connected and that the car is properly plugged in. Third, try rotating the pump handle in either direction. 
  • Finally, check to see if the pump has any leaks by placing a small amount of fuel near the pump and observing the level of leakage.

If none of these steps work, you may need to take your car to a mechanic for further inspection.

Why Mini Cooper Fuel Pump Not Priming

The fuel pump on your Mini Cooper is a mechanical device that can fail for many reasons. The most common cause of fuel pump failure is when the vehicle sits in an environment with high humidity, such as a garage or workshop.

A damaged electrical connection to the fuel pump can also result in not priming. Check your connections and make sure they are secure before you head out for a test drive.

You should also check all other electrical connections in the vehicle and make sure they are securely fastened. 

If the fuel pump has failed completely, you will need to replace it with one. If it’s still under warranty, then simply take it back to where you purchased it, and they will replace it free of charge.

Read more on How Does A Car Act When The Fuel Pump Is Going Out?

Mechanical Fuel Pump Not Priming

Mechanical Fuel Pump Not Priming

Mechanical fuel pumps are designed to deliver fuel at very high pressure, typically between 80 and 160 psi.

As such, they should be primed with gasoline or diesel before use. If the pump has been exposed to dirt or water in the past, it may need to be cleaned before priming.

When an internal combustion engine is first started, the air/fuel mixture must be pushed into the cylinders using the carburetor or fuel injection system.

This is normally done through a mechanical fuel pump (or “priming” pump) that draws fuel from a storage tank and delivers it through a hose connected to one of the gas cap openings on top of each cylinder head.

The most common reason for a fuel pump not priming is a clogged fuel filter. If the filter becomes blocked, it will prevent the pump from getting any fuel through the line. This will cause a mechanical problem with the pump, and it won’t work properly.

To check if your fuel pump is working, remove it from your vehicle and attach an electric tester between the pickup tube and positive terminal on the engine block.

It should start right up as long as there are no other electrical problems with your vehicle’s system or engine itself.

Frequently Asked Questions

1. Why won’t my fuel pump engage?

If your fuel pump is not engaging, there could be a few possible reasons. First, you may need to replace the fuel pump. Second, you may need to reset the fuel pump. Finally, you may need to clear the fuel pump filter.

2. How do I prime my fuel pump?

There are many ways to prime a fuel pump, but the simplest way is to pour gasoline into the tank and sit for a few minutes to help the fuel reach the fuel injectors. You can also prime a fuel pump by pumping the gas pedal to the floor several times.

3. What are the symptoms of a fuel pump not working?

If you are experiencing any of the following symptoms, it may be time to call a technician: your car will not start, your car will not crank over, engine performance issues, or your car will not move.

Fuel pumps are delicate machines and can quickly deteriorate if not properly serviced. If you experience any of these issues, it is important to call a technician as soon as possible to prevent further damage.

4. What are the symptoms of having air in the fuel line?

If you are experiencing any of the following symptoms, it may be time to check your fuel line for air: refusal to start, loss of power, hiccupping, stalling, or rough acceleration.

If you experience any of these symptoms, it is best to take your car in for a check-up. If the problem is minor and can be fixed with a quick repair, then, by all means, go ahead and do so.

5. What to do if the fuel pump won’t prime?

If your fuel pump won’t prime, there are a few things you can do to troubleshoot the issue. First, try priming the pump with a syringe or pumping handle while the car is neutral.

Next, check the fuel lines for any blockages. If the problem persists, you may need to replace the fuel pump.

6. Why won’t my self priming pump prime?

Here are a few causes-

  • Too high A lift for the impeller diameter or pump speed
  • Combustion port plugged
  • The Engine is air Contained.
  • Particles in the Propeller
  • Suction line air leak

7. Why is my fuel pump not firing up?

If your fuel pump is not firing up, several potential causes may be. The first thing you should do is check the fuel lines for any cracks or tears.

If there are any, you will need to repair them before the pump works again. Next, you should check the fuel pump itself for any debris or build-up.

If this is the case, you will need to clean it out before working properly. If all of these tests come back clean, you may need to replace the fuel pump.

8. Why does the fuel pump relay get a spark?

There are a few potential reasons that the fuel pump relay may get a spark. The most common is when the relay contacts the metal fuel lines.

This can cause a short, which can result in a spark. Another potential cause is when the relay contacts a carbon-based part of the fuel system, such as the carbon-based filter.

This can also cause a spark. In either of these cases, the spark can cause the relay to fail, leading to a loss of fuel.


Your car probably has a fuel pump that is supposed to prime the fuel system before you start the engine. But, if it’s not priming, what does that mean for your car?

Priming is when the pump sends a surge of fuel into the system to make sure everything is ready for the engine to run.

If the pump isn’t priming, your car could run out of fuel and require a trip to the mechanic.

In addition, if your car runs out of fuel while you’re driving, it can cause accidents. So, it’s important to check if your fuel pump not priming properly.

Chad Christiansen

Hi, I am Chad Christiansen the chief editor and fuel expert share tips to extend the life of your car Engine. I am expert in additives and product specialist in Synthetic, Gear oil, Diesel, Gasoline. Connect me

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