Top 5 Symptoms Of Faulty Diesel Primer Pump

Naomi O'Colman

Symptoms Of Faulty Diesel Primer Pump

Symptoms Of Faulty Diesel Primer Pump

A diesel primer pump is a component lying between the fuel tank and the engine. Priming the diesel engine is necessary before starting it. When the diesel primer pump malfunctions, the engine cannot be started. The prime pump can fail due to wear and tear or a build-up of dirt within its motor. So, what are the symptoms of a faulty diesel primer pump? Let’s dive in.

What is a diesel primer pump?

The diesel primer pump takes the fuel to the carburetor to start the combustion process. It is located between the fuel tank and the engine. In some cars, the pump can be bypassed; in others, it cannot.

What can go wrong with a diesel primer pump?

Like any other mechanical device, the primer pump can malfunction due to wear and tear. Some of these malfunctions are due to blockage. The blockages are usually caused by dirt or rust in the fuel tank. As a result, the prime pump is unable to suck fuel from the tank and feed it to the engine for combustion.

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Symptoms of faulty diesel primer pump

Make sure you know some common symptoms of a faulty diesel primer pump so that you can diagnose what’s wrong with your car.

#1 Check engine light on

If the “check engine” light is on, there could be something wrong with your car’s prime pump. This could include a faulty fuel tank sending unit or a defective coil. This is one of the most common signs as it’s an engine-related issue.

#2 Hard starting

If your car is not starting for a few minutes after you turn the ignition key, this could mean that there is something wrong with your prime pump. There are several reasons for a hard starting and the primer pump is usually on top of them.

#3 Engine misfire

If the engine has started and is running but is not performing well, it could be due to faulty or worn-out fuel system components. Some of the components that can cause a misfire to include an injector, a fuel pressure regulator, or a faulty fuel pump.

#4 Lack of power

Even after the engine starts, it may still be lacking power. This could mean that there is a fault in the fuel system. The prime pump is usually responsible for supplying fuel from the tank to the carburetor. A defective prime pump may cause insufficient pressure and prevent the engine from working at 100%.

#5 Delayed acceleration

If you have to wait for a few seconds before your car can accelerate properly, this could mean that there’s something wrong with your prime pump. Now, many of these delays can be caused by an airbag. It is therefore imperative that you check your airbag sensor. If there is no functioning bulb, the car will not start or rev up when you turn the ignition key.

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What to do if you see one or more symptoms?

If a car has gone past its service life, it’s time to replace some parts. Fortunately, many parts are available in the market at affordable prices. The prime pump is no exception.

First, you need to find the prime pump in your car. In most cars, the prime pump is located next to the fuel tank. Next, check if you are able to disassemble it and look into its working parts and components. If not, take it to a mechanic or an auto part store for inspection and maintenance.

At this juncture, you should be able to identify if there is a problem with the prime pump of your car. If there is, you should get it replaced as soon as possible to avoid further damage and ensure peace of mind.

How to fix a faulty prime pump?

There are two ways to fix a faulty prime pump depending on your skillset and the number of times you want to perform repairs on your car. The first method involves eliminating the pump from the fuel system. Once this is done, the car will start and run normally. If you want to speed things up, it could be installed in the fuel system itself. However, this will not change how the car runs as it does not eliminate the pump from the system.

The second method involves getting rid of the faulty prime pump without eliminating it from your car’s fuel system. The other option is to remove it completely and replace it with a new one. The procedure will therefore depend on your skill set and the number of times you want to perform repairs.

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The prime pump is an essential part of your car’s fuel system. If there is something wrong with it, you’ll see one or more symptoms as discussed earlier. The good news is that it can be easily replaced and fixed with the right tools and parts.