News - How does a fuel pump work in a car?

How does a fuel pump work in a car?

What is a fuel pump?

The fuel pump is located at the fuel tank and is designed to deliver the required amount of fuel from the tank to the engine at the necessary pressure.


Mechanical fuel pump

Fuel Pump in Older cars with carburetors usually have a mechanical fuel pump (diaphragm pump). This fuel supply pump is driven by a camshaft or distributor shaft. It also draws fuel from the tank and delivers it to the carburetor's float chamber. The supply pressure is approximately 0.2 to 0.3 bar.


Electric fuel pump

The introduction of fuel injection systems in modern engines has necessitated the use of electric fuel pumps. The electric fuel pump supplies fuel to the injectors at a specified pressure. The injectors inject fuel into the intake manifold (manifold injection) or directly into the combustion chamber (gasoline direct injection).

Through manifold injection, an electric fuel pump delivers fuel from the tank to the injectors. For gasoline direct injection, fuel is also delivered from the tank by an electric fuel pump and then compressed to a higher pressure by a high-pressure pump before being supplied to the high-pressure injectors.

Whether the engine is cold or warm, the Electric Fuel Pump (EFP) has the following task: to supply the engine with enough fuel at the pressure required for injection.


Fuel pump cost to replace

With the wide variety of vehicles on the road today, the cost of replacing a fuel pump can range widely.

From basic economy four-cylinder engines to turbocharged V8s designed for performance, fuel pump replacements can range from a few hundred dollars to well over a thousand dollars.

The average cost to replace a fuel pump currently ranges from $220 to $1,100, depending on make, model and year of manufacture.

Symptoms of a bad fuel pump

1. Poor engine operation

If you've owned your own vehicle for many years or have general driving experience, you probably know what a well-running engine sounds like.

When all the systems on the engine work together, it idles quietly at low rpm, accelerates without hesitation, and cruises the highway with ease.

However, if the engine isn't getting enough gas from the fuel pump, it won't be able to generate power and work as intended, and you will feel and hear the difference.

When you start your car, if the engine is crackling or idling unevenly, it may not be receiving the amount of fuel it needs, or it may not be receiving fuel at the proper rate. Not only does this make for an unpleasant driving experience, but it can cause damage to the inside of the engine.

2. The vehicle does not start

It's a hassle when you need to be somewhere and your car won't start. While there could be a number of reasons why the engine won't start, from the battery to the ignition coil, a fuel pump failure is one of the most likely causes.

3. Engine overheating

An overheating engine can also be a symptom of a failing fuel pump. A damaged fuel pump can overheat and fail to deliver enough gas to the engine, causing the engine to overheat and stall while driving.

In this case, your vehicle may restart after overheating and shutting down, only to do the same thing half an hour later. This condition is a common sign of a bad fuel pump.

4. The speed can't keep up

Smooth, consistent engine performance requires a healthy fuel supply. When the fuel pump fails, not enough gasoline reaches the engine, losing the ability to run at constant rpm.

When you are driving at a steady speed and notice the engine misfiring or losing power, the fuel pump may be faulty. It may feel like the engine is running out of fuel, when in fact the fuel pump is not delivering fuel from the tank.

5. Reduced fuel efficiency

Filling up your gas tank costs money, and getting the best mileage can help keep your expenses down. It's a nice feeling to find different ways to extend gas mileage, whether it's lightening the throttle or keeping the tires properly inflated.

However, if you find that your car is using more gas than you expected, there may be a problem with the fuel pump. In this case, the pump may deliver too much gas to the engine, depleting the tank prematurely.

A fuel pump is just one of many components needed for reliable, safe driving. When you're in the market for a used car, you want a car that's been fully inspected, has all the parts in good condition, and will stand the test of time.

Post time: Jan-04-2023