What does a fuel pump relay do?

The fuel pump relay is the electronic switch that controls power to the fuel pump. It is found on virtually all vehicles with an internal combustion engine and is often located in the fuse box which can be found in the engine bay. The fuel pump relay is also responsible for helping your vehicle to start. The relay activates the fuel pump to pressurise the fuel system as you turn the key.

The fuel pump is a small pump which sends the fuel from the tank to the engine. The pump may be mechanically worked by the engine, but on most modern cars it’s electrically-powered. In this case it’s usually found next to or even inside the fuel tank.

This process of pumping fuel from the tank to the engine is essential in the smooth running of your vehicle, therefore a faulty fuel pump relay will cause major performance and drivability issues with your vehicle.

Volvo

Volvo Cars is a Swedish luxury vehicle manufacturer, established in April 1927, over 90 years ago.

How popular is Volvo in the United Kingdom?

With around 645k cars on the roads in the UK today, Volvo is a considerable contributor to the UK motor industry.

With a steady rise in status from the boxy estate models popular in the 1970s, 1980s and 1990s, Volvo now produces a strong, executive range of luxury, performance vehicles.

Luxurious executive saloons, estate cars and SUVs

Sticking to the market they understand best, Volvo produces a small range of estate cars and a selection of bang-on-trend SUVs, complimented by 2 luxury saloon models. In other words, Volvo makes cars for ‘grown-up’ drivers where it knows its customers inside out.

Volvo: Exceptional aims for in-car safety

One of Volvo’s key visions is to provide a level of unrivalled safety inside their vehicles and has proven to be a dedicated leader in the field. Their current vision is that nobody should be seriously injured or killed in a new Volvo car by 2020.

Pursuing perfection through Volvo technology

The ethos behind Volvo reaches further than just selling units and making a profit. By putting their customers first, they have committed to creating vehicles where ownership gives quality time back to their drivers, are environmentally efficient and exceptionally safe.

Using modern technology and striving to develop the systems to lead the field, is something they take very seriously. After all, this is the company that brought drivers:

• The 3-point safety seatbelt

• The Lambda Sond emissions detector responsible for reducing harmful fumes by 90%

• Side impact, whiplash, and roll-over protection

• Blind spot systems

• City safety scanning

• Pedestrian detection

• Auto-braking

How often should a fuel pump relay need replacing?

There is no set lifespan of a fuel pump relay, however the relay is designed to last the life of the car, but due to its constant use and the high temperatures it is exposed to, it will not usually last that long. Over time, the fuel pump relay may begin to show signs of wear and will have to be replaced.

The most commonly damaged portions of the fuel pump relay that tend to malfunction first are the coil and contact points. Usually, these parts of the relay will begin to oxidise and rust over time.

The law, vehicle regulations and your MOT

If the fuel system is not working properly, this may result in an MOT fail. Similarly, if a failing fuel pump relay has caused your check engine light to illuminate, this could lead to an advisory or failure.

What causes a fuel pump relay to break?

The fuel pump relay can fail for many reasons, from dust to electrical power surges, or a blown fuse to a fault in the pump. Many things can affect the functionality of the fuel pump relay.

What are the signs of a failing fuel pump relay?

Usually, there a few signs you can look for:

• Poor fuel economy

• Trouble starting your car

• Poor engine performance - stalling, poor acceleration, rough idling

• Check engine light

• Car stops whilst driving

How often should you replace your fuel pump relay?

There is typically no maintenance schedule for fuel pump relay replacement. However, it may not be a bad idea to replace the fuel pump and the relay on an older, high mileage vehicle. Regularly maintaining small components such as the fuel pump relay could save you costly repair bills down the line.

What happens during a fuel pump relay replacement?

During the repair our certified mechanics will:

• Inspect the entire fuel system and test it for any issues

• They will then locate the fuse box, usually found in the engine bay

• If necessary, they will remove the old relay and replace it with a new one

• They will they retest the fuel system and check the fuel pump is working

What is the average life of a fuel pump relay?

There is no set lifespan of a fuel pump relay, however over time, the fuel pump relay can begin to show signs of wear and will have to be replaced. The fuel pump relay is designed to last the life of the car, but due to its constant use and the high temperatures it is exposed to, it will not usually last that long.

The most commonly damaged portions of the fuel pump relay that tend to malfunction first are the coil and contact points. Usually, these parts of the relay will begin to oxidise and rust over time.

Can you drive with a broken fuel pump relay?

It is best to avoid driving with a failing fuel pump relay. If the fuel pump relay has an issue, power may be randomly cut off to the fuel pump, which will cause the engine to stall whilst driving. Problems with your fuel pump relay will also result in frequent stalling and poor fuel economy, problems which are inconvenient and costly. It’s always best to have a faulty fuel pump relay checked as soon as possible to avoid these issues.

What happens if you don't change the fuel pump relay?

If the fuel pump relay has an issue, power may be randomly cut off to the fuel pump, which will cause the engine to stall whilst driving. Problems with the relay may also result in frequent stalling and poor fuel economy, which are both inconvenient and costly.