The car fuel system

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.

  • A sputtering engine

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.

  • Power loss

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.

  • A surging engine

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.

Advice for buyers of brand new 72-registration cars

Kia Sportage - 72-registration

Every March 1 and September 1 in the UK the date identifier on new car number plates changes.

So, this September the current ’22’ plate (eg AB22 CDE) will change to ’72’ (eg AB72 CDE).

Traditionally, more new cars were sold in March and September than the rest of the year combined as drivers raced to drive new cars with the latest registration plate.

However, the global shortage of tiny semiconductor computer chips has meant that demand is now far outstripping supply, so sales in general have taken a hgit.

However, if you’re not put off longer than usual waiting times, The Motor Ombudsman (which is an independent and impartial ombudsman dedicated solely to the automotive sector), has some great advice.

Shop around and do your research
Spending time doing your research online or visiting showrooms can pay off, as some retailers may run promotional offers to help with the cost of ownership. Test driving cars of interest is also an effective way of knowing which makes and models best suit your requirements and lifestyle.

It is just as important to ensure that your chosen retailer is accredited to The Motor Ombudsman’s Vehicle Sales Code, as this shows that the business is adhering to the highest standards of service. In addition, should there be a complaint that you cannot conclude directly with a seller in the first instance, you will also have access to The Motor Ombudsman’s free-of-charge, independent and impartial Alternative Dispute Resolution (ADR) service.

Expenses for running and maintaining a car should be budgeted for
It is not only the initial price tag of the car which matters in terms of being affordable. Post-purchase, there are running and maintenance costs to take into account, such as monthly finance payments, annual servicing, fuel or electric charging tariffs. Many new cars are offered with incentives, such as free insurance, road tax (where applicable) and breakdown cover, but once expired after the initial defined term, these ownership expenses will also need to be paid for.

Virtual online vehicle purchases are governed by specific legislation
Buying a new car online from start to finish over the internet, instead of visiting retailer premises at any point during the purchase process, including for a test drive, is known as a “distance sale”. In this scenario, the sales transaction is governed by the Consumer Contracts (Information, Cancellation and Additional Charges) Regulations 2013. For example, when buying a vehicle on the internet, you have 14 days to return the car from the date of delivery if you change your mind, but it is important to bear in mind that there may be deductions for usage if you have driven the car before deciding to hand it back.

Electric vehicles are becoming more prominent
With petrol and diesel prices recently hitting record highs on forecourts across the country, buying an electric vehicle (EV) is becoming a more popular ownership proposition. With the number of electric models on the market increasing, there is far more choice in terms of budget, range, battery capacity and equipment. Before buying an EV, it useful to think about factors, such as where it can be charged – i.e. on the street or a driveway, and where and how you will be driving it, namely whether it will be used predominantly for short journeys and errands, or to travel longer distances.

New cars mean you can choose the specification
One of the main advantages of buying a new car straight from the factory, as opposed to one that is second hand, is that you are the very first owner. This means that you can choose the vehicle’s exact specification according to your budget and taste, including the interior and exterior colour, the size of engine (for a petrol or diesel model), or battery capacity and range (for an electric car), and whether the car is fitted with automatic or manual transmission, for example.

Tow the line
If you are looking to buy a vehicle to tow a trailer, horse box or caravan, for work or leisure purposes, it is worth asking whether accessories, such as a towbar and wiring, can be fitted to the model you are interested in, and to find out the maximum weight that can be pulled safely by the car. For first time “tow-ers”, or for those simply needing a refresher, training is available via providers across the UK.

You may have to wait for delivery
With fewer new cars being produced due to global component shortages, and semiconductor chips being one of the most in-demand parts, it is worth planning in advance in terms of when you would be looking to take delivery of your vehicle, as it could take several months for it to arrive.

Furthermore, there is the possibility that the date specified by the retailer on the order form may also change according to the manufacturer’s build schedule, so take the time to read any documentation and terms and conditions carefully to understand the implications of any timing changes prior to putting down a deposit. You may find that the specification that you have selected is not complete at the point of delivery. In most cases, this should be rectified as the parts become available, and the retailer should keep you updated about this.

Technology varies by make, model and fuel type
With the wide variety of makes and models on the market today, the way that in-car controls are used (i.e. via a touchscreen or manual dials, for example) varies by brand. The equipment which comes as part of the standard specification, and what is available as paid-for extras or options, can also be different.

With many elements of the vehicle now dependent on software and electronics to operate, it can be helpful at the point of purchase to enquire about any steps that need to be taken to keep systems up to date or be upgraded via recommended downloads, such as satellite navigation maps. Some downloads may be activated remotely via the manufacturer’s “over-the-air” updates, where no further action is required. In addition, there may be subscription services that, for the first year are included in the car, but then may incur a charge for future use. Some vehicle functions may be controlled via a smartphone app (e.g. for electric vehicles), so it is worth checking that your device is compatible, and that you will be comfortable using this kind of technology.

Warranties come as standard for new cars
The advantage of buying new is that, cars come with a manufacturer’s warranty as part of the purchase. These will vary in duration (i.e. three to seven years) or for the total mileage that is covered under the agreement (e.g. up to 100,000). Warranties are designed to cover the cost of rectifying mechanical failures that occur as a result of a defect during the build process. It is advisable to read the policy fully, to be up to speed with any exclusions, such as for wear and tear items, including tyres and brake discs.

It is also commonplace for manufacturers to provide paint and anti-corrosion warranties, although these will often be for a more limited period, whilst electric models may also come with a separate battery warranty for the retention of a percentage of its capacity for a specific number of years or miles.

On handover day, check and understand the vehicle
The day that you are handed the keys to your new car is often an exciting time. However, before driving off the forecourt, it is worth spending the time doing a walk-around with a member of staff, to ensure that you are satisfied with the interior and exterior condition of the car, that all documentation, including the handbook is present, and that you are comfortable with how any controls and systems work, as these can differ between models.

Bill Fennell, Chief Ombudsman and Managing Director of The Motor Ombudsman, added: “Buying a big ticket item, such as a new car, is a significant commitment. It is therefore important that consumers spend time doing their research to select both the right car and retailer, spend within their means, and plan ahead both in terms of longer-term affordability, and when they will need a new car due to the extended lead times.”

Why you should use specially formulated engine lubricants for classic cars

By Mark Powell, Business Unit Director at Broughton Lubricants

Working on a classic car is an endlessly rewarding hobby, whether you have significant experience with older engines or are picking things up as you go. If you are restoring a vintage vehicle to make it road-worthy, intending to display it in competition or just working on it for your personal satisfaction, there is a lot you will need to learn about the inner workings of the engine. Even if you are experienced with contemporary cars, older vehicles have very different needs and there are limited resources available to help you to learn what you need.

This is especially the case when it comes to choosing the right engine fluids. You may be aware of this when it comes to fuel – from this year, petrol in the UK will switch from E5 (which contains about 5% ethanol) to E10 (with an ethanol content of 10%) and it has been well publicised that this fuel may be unsuitable for many models of classic cars. E10 fuel is able to corrode flexible fuel lines, seals and gaskets, which can lead to dangerous fuel leaks, fires and other risks.

However, you may be unaware that the same applies to motor oil. Like petrol, the formulation of oil has changed significantly over time, both in response to climate change concerns and to keep up with the latest trends in engineering. Older vehicles may have larger oil galleries, lower revving and low-pressure, gear-driven oil pumps, meaning that you will need an oil with very different properties from contemporary products.

While there is no specific definition of a classic car in the UK, HMRC considers any car over 15 years old to be ‘classic’, while for some it is taken to mean cars that are more than 40 years old, which are not subject to road tax or MOT tests. Because there is a wide variance in the types of vehicles that are considered ‘classic’ under these broad definitions, it is important to understand product specifications and the needs of your particular engine when purchasing engine oil or other automotive fluids. Many people who restore classic cars begin with a Haynes Manual, but for older cars a lot of the information may be out of date, and automotive lubricant products are regularly discontinued.

Fusing modern and classic engineering

Thankfully, many manufacturers now carry ranges of products that are precision-engineered for vintage and classic engines, enabling you to find a suitable automotive fluid for your needs long after the product listed in your Haynes’ Manual has been discontinued. This removes the risks of using products designed for modern engines, but it can also be difficult to know exactly what oil you need without support, so it is worthwhile to speak to an expert if you are buying for the first time.

While these products meet the technical requirements of older engines, they also contain additives designed to improve the performance of classic and vintage vehicles, and help them to operate effectively under road or competition conditions. Older engines typically need more viscous engine oil than newer engines, and so these ‘classic’ products are formulated to deliver this. For example, additives may be formulated to enable oil to work at low temperatures without the buildup of viscous ‘sludge’, or to reduce wear throughout the engine. In this way, products like those in Castrol’s Classic range deliver the advantages of modern engine fluids while being designed to fulfil the requirements of older vehicles, for fluids like gear oil, engine oil and transmission oil. This also includes a lead replacement for petrol engines, which enables the use of modern petroleum fuel in these older vehicles.

Ultimately, the advantages of choosing an appropriate product are clear: reduced wear on the engine (especially on parts that can be difficult to replace), more efficient operation and reduced need for maintenance or oil replacement. It is always true that selecting an oil or lubricant that is precisely engineered for your requirements can deliver improved performance, but this is especially the case for the unique challenge of powering a vintage or classic engine.

Are young Brits pushing the limits too far?

Guest Blogger

11 hours ago
Auto Blog

New research reveals the most common traffic offences by young drivers in the UK

With time, driving becomes second nature for the majority of us. That ‘new driver’ feeling – the focus and concentration needed to execute the simplest of manoeuvres – soon fades away.

Mistakes are easily made in the earlier stages of our driving careers so, with that in mind, Hastings Direct have carried out a study exploring the most common traffic offences and mistakes that young drivers make, to understand more about their driving habits.

Top 10 most common traffic offences for young Brits (16-25-year-olds)

FOI data from the DVLA reveals the top ten offences that younger drivers are most guilty of and the total number of offences for this age group between the dates 01/01/2020 and 31/12/2021.

  1. Exceeding statutory speed limit on a public road (128,677 offences)
  2. Using a vehicle uninsured against third party risks (56,789 offences)
  3. Exceeding speed limit on a motorway (33,055 offences)
  4. Driving otherwise than in accordance with a licence (30,658 offences)
  5. Driving or attempting to drive with alcohol level above limit (12,068 offences)
  6. Failure to give information as to identity of driver etc (11,631 offences)
  7. Driving or attempting to drive with drug level above the specified limit (10,529 offences)
  8. Driving without due care and attention (6,426 offences)
  9. Driving while disqualified by order of court (5,228 offences)
  10. Using a vehicle with defective tyre(s) (4,420 offences)

4 in 10 traffic offences committed by young drivers are related to speeding

The data shows that young drivers make the mistake of driving too fast both on public roads and motorways, with each of these offences appearing in the top three. Exceeding the statutory speed limit on a public road (1) accounts for almost 40% of the top traffic offences for those aged 16-25, making it the most common offence by far. Combined with motorway speeding (3), the research shows that half of all driving offences by this age group are due to driving too fast.

Drug and alcohol-related traffic offences amongst the most common for young Brits

The top ten traffic offences resulting from the new research reveal that speed is not the only limit young drivers seem willing to push, with drunk driving and driving with drug levels above the limit accounting for almost 7% of the most common traffic offences – almost 23,000 in total.

However, those two offences combined (5 & 7) don’t come close to the second most common offence of using a vehicle uninsured against third-party risks. Borrowing a car without insurance catches out close to 57,000 young drivers – more than double the offences relating to alcohol and drug levels.

Over 30,000 young drivers caught without a licence

This issue is particularly prevalent amongst the younger age groups, accounting for 36% of offences for drivers aged 16, becoming less of an issue for those aged 25 (7%). This impatience to hit the road is unlikely to be helped by the current issues young drivers face when it comes to booking a test, with backlogs caused by the pandemic leaving some learners with a six month wait for a test.

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Looking for the most economical car? Here’s our top picks!

Yaris Cross

Looking for your next new car? There are a number of important things to consider before wading in online (or in store) and making a financial commitment.

But first you should look at a car valuation, to figure out how much your old motor is worth. Ultimately you’ve gotta know how much money you have to play with before doing much more research.

Done that? Well now you’ve gotta make sure a car has enough room for you and your activities. Three kids and a dog? You won’t want a city car. Equally, it’s got to have an interior you understand and like. After all, you’ll be in it most days. Oh and then there’s the way it drives, the way it looks and how jealous you want to make your neighbours. A lot to be getting on with in other words.

One thing that’s often overlooked is the economy. This isn’t exactly a sexy consideration, but is one that can save you hundreds of pounds a year. Plus you’ll need to do fewer stops at your local filling station.

Instead of just reeling off the most economical cars currently on sale, below you’ll find that  we’ve detailed our top five picks separated into categories. There’s the best supermini, best family hatchback, best SUV, best estate and best saloon.

And it’s worth noting our list is based on official WLTP testing figures, and doesn’t include plug-in hybrid cars. This list is for petrol and diesel cars with or without hybridisation.

Best supermini

Peugeot 208 – 71.4mpg

The 1.5-litre diesel engine in this Pug will officially do more than 70mpg. That’s pretty impressive. Sure, the 0-62mph time of 10.2 seconds won’t get the heart racing, but it’s a muscular engine and is great for motorway work.

The cockpit is impressive too. It has Peugeot’s clever 3D digital display that projects important info (like MPG) onto the windscreen in front. It works really well and is super easy to read.

Best family hatchback

VW Golf – 68.9mpg

Another diesel on the list, this time a 2.0-litre courtesy of VW. Officially it’ll do close to 70mpg plus it’s punchy. Overtaking on a b-road doesn’t require minutes of careful planning.

The sharply styled Golf is a bit bland inside, but it has all the connectivity tech you could want. Plus the fit and finish is good.

Best SUV

Toyota Yaris Cross – 68.8mpg

The best SUV was always going to be a little one rather than a massive one. But the Yaris Cross is practical enough, plus it has a revvy little 1.5-litre hybrid petrol engine.

It might look like ‘just’ a Yaris on stilts. But the Yaris Cross has more head room, a better infotainment system, plus a bigger boot than the regular Yaris. And it’s not a whole lot more money.

Best estate

Peugeot 308 SW – 65.6mpg 

Don’t be fooled by the SW badge. This is a good old fashioned estate with a 608-litre boot and room for five.

Looks good though, doesn’t it? Very unlike the boxy estates of the eighties. MPG is strong too, with more than 65 mpg on offer from its diesel engine.

Best saloon

Skoda Octavia – 65.7mpg

Okay we’re cheating here slightly. The Octavia is technically a hatchback, but it looks like a saloon with its sloping rear.

There’s loads of rear space, plus a huge boot. The interior is posh, and with big wheels, it looks great too. The 2.0-litre diesel is the one to go for here.