It goes without saying that your car wouldn’t go very far without the fuel that powers it. The fuel plays a vital role in the combustion process. A precise mixture of fuel and air is ignited inside the engine cylinders, creating the energy needed to propel the car. The fuel system consists of all the components required to deliver the fuel supply from the tank at the rear all the way to the engine, including the lines, fuel pump, fuel filter, fuel pressure regulator and the injectors.
Different kinds of modern fuel systems use different methods of injection, such as direct injection, indirect injection, multipoint injection and throttle body injection. Back in the day, most vehicles used a carburetor to send the air-fuel mixture to the internal combustion engine. The component consists of two pipes, one for air and one for fuel, valves, and a float bowl. It adjusts the air-fuel mixture by creating a vacuum, which sucks in the fuel. The problem with this is that it isn’t the most accurate or efficient method for mixing fuel and carburetors would often have a slight lag, resulting in a slower throttle response. Injection systems addressed these inefficiencies, which is why they had largely replaced the carburetor by the early 1990s. However, these components are still found on some classic models today.
Image of a fuel pump taken from Autopartspro.co.uk
What exactly does the fuel pump do? How does it work?
Now that we know more about the car fuel system, let’s discuss one of its most vital components – the fuel pump. For the majority of vehicles today, the pump is located in the fuel tank. Its primary function is to force the fuel out of the tank and through the fuel lines. Some systems have multiple pumps, ensuring that the system always has access to fuel, as it can often move from one end of the tank to another when the car is travelling on an incline or making sharp turns. The fuel is pumped through the lines, passing through the fuel filter/s before reaching the engine cylinders.
However, there are a number of things that can go wrong here. For example, if you use low-quality fuel or regularly drive with very low fuel levels, you increase the risk of pump contamination which can lead to failure. The component can be damaged or worn over time, or become clogged. Electrical problems can also occur as a result of loose or rusty connectors and faulty wires. When the fuel pump isn’t working as it should be, it can have a significant impact on the speed, power, and performance of the vehicle as the engine won’t be receiving a reliable supply of petrol or diesel.
Diagnosing a faulty fuel pump
The first step to diagnosing a bad fuel pump is to be able to spot the telltale signs of a fault.
Symptoms of a bad fuel pump:
- Difficulty starting the engine
This can occur as a result of a lack of pressure due to a weakened pump. Depending on the severity of the problem, the motor may not start at all. There are a number of other possible causes for this, including clogged fuel lines or worn components. You can check for pump problems using a fuel pressure gauge or a diagnostic scanner.
You may notice that your engine starts to sputter once you’ve reached a high speed. This is a key indicator that the power unit is not getting enough fuel, possibly due to a clogged or defective pump.
- A whining noise coming from the fuel tank
Modern electric pumps should not be audible. A loud whining noise is a common sign of a failing or worn fuel pump.
This may occur when the vehicle is under stress, such as when it is ascending a steep hill or carrying a heavy load. If there isn’t enough fuel, there could be a sudden loss of power.
On the flipside, it’s possible that a faulty pump delivers too much fuel, causing the engine power to surge and then drop suddenly. This can pose a safety risk on the road.
Source: automotiveblog.co.uk
Darrell
