Drivers are being urged to take better care of their engines – and it could be as simple as heading down the motorway now and then. Experts have warned that cautious, slow driving habits may actually be doing more harm than good, increasing the risk of engine damage caused by carbon build-up – often referred to by mechanics as “black death.”

Most motorists try to protect their cars by driving gently around town, but this can unintentionally lead to long-term problems. One of the biggest risks is the accumulation of carbon deposits, which clog internal components, reduce fuel efficiency, and can eventually lead to engine failure.

If you’re constantly driving at low speeds – especially for short journeys – your engine never gets hot enough to burn off carbon deposits. Over time, this can lead to a build-up inside your valves, pistons and exhaust system.

Known as “black death” because of its thick, dark appearance, the deposits are a by-product of unburnt fuel and poor engine circulation. Left unchecked, they can harden and cause serious damage.

In the worst-case scenario, carbon build-up can cause your engine to seize – and replacing that could cost thousands.

Thankfully, there’s a simple solution – and it doesn’t cost a penny.

Modern engines are designed to be run at higher speeds from time to time. Taking your car for a steady drive on the motorway helps heat the engine fully and allows fuel to clean and lubricate components.

Petrol, when forced through the system at higher pressure, can act as a natural solvent – cleaning valves and piston rings as it goes.

Another warning sign to look out for is white foam or froth under the oil cap, which could indicate water condensation in the engine oil, often caused by short trips where the engine doesn’t heat up properly.

If you take your oil cap off and notice a milky substance, that’s usually a sign your engine isn’t getting hot enough to burn off moisture. It’s not necessarily a serious fault, but it can lead to long-term problems if ignored.

Again, a regular long-distance drive at a steady speed can resolve the issue. When you drive at motorway speed for 45 minutes to an hour, the heat generated by the engine is enough to evaporate condensation and prevent that build-up. Keeping up with maintenance and using preventative measures like these can keep your vehicle in a better condition for longer, and hopefully save your bank balance from taking a big hit too.

Mechanics Warn Drivers to Beat Engine ‘Black Death’ with This Simple Habit

Bumper has successfully completed its Series B extension round, raising an additional £8 million in equity funding. This marks the second extension to its Series B round, bringing the total investment to £20 million.

The round attracted the continued support from leading automotive and mobility investors, including Autotech Ventures, Suzuki Global Ventures, Porsche Ventures, JLR’s InMotion Ventures and Shell Ventures.

The completion of this latest funding round coincides with Bumper marking its tenth anniversary with a refreshed corporate brand identity and the launch of an all-new website with greater functionality for both dealer partners and car owners.

Bumper will use the new funding to launch the Bumper Pro platform and AutoBI services across the UK and Europe and support strategic hiring to scale the company’s operations.

Bumper Pro enables automotive retailers to use Bumper’s direct payment solutions to reduce card transaction fees and automate back-office workflows. AutoBI, a business acquired by Bumper last year, provides real-time business intelligence tools for car retailers and OEMs.

James Jackson, Co-Founder and Chief Executive Officer of Bumper, said: “This investment is a strong vote of confidence from existing investors in our ambitious growth trajectory, long-term vision and our amazing team.

“We are now operationally profitable and on track to surpass £1 billion in gross merchandise value (GMV) in 2025, representing a tripling of our GMV year-on-year. This momentum is driven by our expanding suite of services that deliver quantifiable value to automotive retailers and OEMs.

“Ten years ago, Bumper launched as a provider of interest-free repair financing for car owners. Today, it has evolved into a comprehensive digital payments and software as a service (SaaS) platform for the automotive retailing sector, with products designed to streamline dealer operations, reduce costs and enhance customer experiences.”

Tony Rimas, Venture Partner of Autotech Ventures, said: “We first invested in Bumper in 2021, attracted by its industry-leading buy now, pay later (BNPL) product and penetration in the UK dealer sector. Since then, we have been impressed by its remarkable revenue growth in the UK and across Europe, its expanded portfolio of payment solutions and the team’s ability to execute on its ambitious plans.

“We’re delighted to support the next phase of Bumper’s growth and are particularly excited by the opportunities presented by its acquisition of AutoBI and Cocoon Payments and the rollout of the game-changing Bumper Pro platform.” 

Kaihei Takagi, Director of Suzuki Global Ventures said: "We are very excited to continue supporting Bumper’s growth, following our initial investment, in this Series B extension. As a result of Bumper’s proactive M&A growth strategy, we have been able to engage in broader strategic discussions beyond just Buy Now, Pay Later (BNPL), including areas of potential collaboration with Suzuki Motor Corporation. 

“We look forward to deepening these strategic conversations and supporting Bumper’s continued expansion across Europe, Japan and other regions."

Bumper raises £8 million in Series B extension to accelerate expansion and product rollout

When the temperature starts to climb in the summer, your car feels it too. Engines overheat. Air cons give up. And let’s not even talk about accidentally touching the metal on your seatbelt. 

Whether you're commuting or road-tripping, driving in a UK heatwave takes a bit of prep. Here are 5 tips to make your drive a little bit easier when the temps start rising. 

Driving in a heatwave can quickly go from uncomfortable to unbearable, unless you know how to keep your car (and yourself) cool.

Parking in the right spot can make a massive difference in a heatwave. Look for shade wherever you can find it: under trees, beside tall buildings – it might even be worth paying to park in a multi-storey car park. Even partial shade keeps your cabin temperature down and protects the interior from UV damage. 

No shade around? Make your own! A reflective windscreen cover can knock several degrees off your car’s internal temperature. You can also throw a towel across your steering wheel to stop it from heating up too much.

Open all the doors (or at least the front windows) and let that trapped heat escape for a minute or two. You’ll be surprised by how much cooler it feels straight away. This also gives your air con a better head start. Instead of working overtime, it can kick into action fast and more efficiently, keeping you cooler and allowing for better fuel efficiency when driving in a heatwave.

Once it starts to cool, close the window and switch the A/C to ‘Recirculation Mode’. This stops hot outside air from coming in and focuses and cools the air faster, taking less effort from the A/C and saving you fuel. This is especially important if you’re stuck in traffic or on a long drive. 

 If your car has a ‘max A/C’ button, use it to blast cool air through your car quickly. Once comfortable, dial it back to normal to stay comfortable without overworking the system. 

Are your car seats made of leather, vinyl or a dark fabric? These can absorb and trap heat especially well. And once they’re hot, they stay hot – not great if you’re driving in a heatwave. 

That’s where a cooling seat cover comes in. These handy add-ons reflect heat, improve airflow, and make your seats feel instantly cooler to the touch. Some even plug in and use fans to circulate air around your back and legs. No matter if you have a high-tech ventilated cushion or just a simple breathable mesh cover, they’re a simple, affordable way to make driving in a heatwave much more bearable.

5. Keep your fuel tank at least half full 

No one likes seeing the low fuel light, but it’s even more of an issue when driving in a heatwave. When the tank’s nearly empty, the heat can make your fuel evaporate faster, creating vapour and adding pressure on your fuel system. On top of that, your fuel pump needs to stay cool, which it does by sitting in the fuel itself. Less fuel means less cooling, which can make the pump overheat and wear out quicker. 

Before you go anywhere, give your car a few simple checks to save you from getting stuck later:

These small checks only take a few minutes but can make a big difference when driving in a heatwave, helping you keep cool and stopping small issues from turning into expensive problems.

Don’t let the heat catch you out with Bumper repair finance

If you’ve been driving in a heatwave and it’s taken a toll on your car, Bumper is here to help with simple 

. Whether it’s a blown tyre, failing air con, or unexpected engine trouble, split the repair cost into easy monthly instalments with 0% interest. Most applications are approved in minutes with a soft credit check, and you can apply online or directly with over 5,000 trusted partner garages.

There’s no exact number for when it gets too hot to drive, but when your cabin starts reaching 30°C, that’s when it can get dangerous. Keep a thermometer in your car or check the dashboard reading. If it feels too hot to function, it probably is.

What weather conditions should you not drive in?

If the outside looks like any of the following, it might be best to stay indoors: 

You can get heatstroke when driving. And it can happen faster than you think. Long journeys without proper ventilation or staying hydrated can push your body past its limit. Look out for early warning signs like: 

Top 5 tips for driving in a heatwave

If your car’s air conditioning has started to smell damp, musty, or even burnt, it could be more than just an unpleasant whiff; it might be the early sign of a serious problem. Failing to act quickly could result in a much bigger bill later down the road.

While many drivers assume a bad smell is harmless, the reality is quite different. One of the most common causes of a foul smell from your air conditioning is the build-up of mould or bacteria inside the system. This tends to happen when the system hasn’t been used for a while or hasn’t been serviced properly.

Moisture inside the unit – particularly around the evaporator coil – creates the perfect breeding ground for bacteria. Once that bacteria takes hold, every time you switch the air conditioning on, it circulates musty air through the cabin.

More concerning, however, is the presence of a burning or electrical smell, which may point to something more dangerous. That kind of odour can suggest overheating components or wiring faults. These are far more serious and shouldn’t be ignored – it’s definitely time to book in with a qualified mechanic.

If the smell is mild and not accompanied by any other warning signs, drivers can sometimes tackle it themselves. Cleaning the drain pan and evaporator coil may help reduce odours, especially if it’s simply stale air. But if the smell sticks around or worsens, don’t try to mask it – get a professional opinion before more damage is done.

Neglecting early warning signs can prove costly. Something as simple as mould can eventually damage components if left untreated. What could have been a low-cost clean-up might turn into a complete system replacement.

Often, what stops people from acting fast is the cost. We know that unexpected car repairs can cause financial strain, which is why we offer interest-free monthly payment plans. It means drivers can get their cars sorted straight away without putting it off due to cost.

The message is clear: if your air conditioning smells off, don’t ignore it. It might just need a clean – or it might be something much more serious. Either way, you’ll save money and stress by sorting it sooner rather than later.

Why Your Car’s Air Conditioning Smells – and How to Fix It!

We're highlighting a range of budget-friendly SUVs, ideal for families looking for space, efficiency, and everyday comfort. And best of all, they're all typically available for under £10,000.

Many families need vehicles that are spacious, economical, and stylish, and SUVs in this price range really tick all those boxes. You don’t need to break the bank to find something practical that still feels modern and well-equipped.

The Kia Sportage has earned a strong reputation for being one of the most dependable and family-friendly SUVs on the market. With its bold styling and well-laid-out cabin, it's perfect for day-to-day use and longer road trips.

The Kia Sportage is a superb choice for families, with its spacious design, solid build quality and low running costs. Its elevated seating position offers excellent visibility, and many models come with useful features such as Bluetooth, cruise control and air conditioning.

The Renault Kadjar is known for its modern design and tech-forward features, making it ideal for families who want practicality with a touch of sophistication. It offers a comfortable ride with generous space for both passengers and luggage.

Families will love the Kadjar’s blend of practicality and technology. It often includes features like touchscreen infotainment systems, smartphone integration, and driver assistance tools, all wrapped in a sleek, modern design.

The Mazda CX-5 stands out for combining a premium feel with impressive driving dynamics. Its interior is thoughtfully designed with family use in mind, while the ride quality is smooth and refined.

The Mazda CX-5 is known for its smooth performance and spacious interior, making it an ideal family vehicle. It’s also one of the more fuel-efficient options in its class, making it a smart long-term investment for households.

The MG ZS offers excellent value for money and has grown in popularity thanks to its modern features and user-friendly design. It’s a compact SUV that punches above its weight in terms of interior quality and practicality.

The MG ZS brings a fresh, youthful feel to the SUV market. With its smart infotainment systems and thoughtful interior layout, it’s a strong option for families who want something modern and reliable.

The Ford EcoSport is a compact SUV that delivers flexibility, especially for families navigating city and suburban life. Its higher driving position and versatile seating make it suitable for school runs, shopping trips, and weekend getaways.

The Ford EcoSport is a practical choice with its compact, roomy design. It’s easy to drive, offers great visibility, and often comes with tech features that keep everyone connected and comfortable.

Stylish SUVs That Are ‘Economical’ and Perfect for Families for Under £10,000

Looking for a stylish and reliable car that fits your budget? Car repair finance experts at Bumper have highlighted three standout hatchbacks that typically retail for under £10,000 - offering great value for drivers who don’t want to compromise on quality or driving enjoyment.

Many people think sporty means expensive, but there are some fantastic hatchbacks that combine a fun driving experience with low running costs. These models are ideal for everyday use while still delivering sharp design and responsive performance."

The Vauxhall Corsa is a longstanding favourite among British drivers thanks to its compact size, affordability, and punchy styling. With its sporty silhouette and comfortable ride, it's a strong contender for those looking for a city-friendly car with personality.

The Corsa blends urban practicality with youthful design and reliability. It’s well-suited for first-time buyers or anyone seeking a stylish daily runaround with low maintenance costs.

The Volkswagen Polo is well known for offering premium touches in a compact package. Praised for its build quality and refined driving feel, it stands out in the hatchback market as a more grown-up option without the premium price tag.

The Polo delivers a smooth, confident ride and feels like a step above many competitors in terms of interior finish and comfort. It’s a brilliant option for drivers who want a practical hatchback that still feels refined and well-equipped.

The BMW 1 Series brings a sporty, rear-wheel-drive experience to the hatchback category - a rarity at this price point. With bold styling and a reputation for strong performance, it’s perfect for drivers who want a more engaging, dynamic feel on the road.

The 1 Series stands out for those wanting something a bit more premium. It offers responsive handling, a well-crafted interior, and that iconic BMW driving experience in a more accessible package.

3 Sporty Hatchbacks You Can Buy Right Now for Under £10,000

With the most recent heatwaves behind us for now, the UK now seems to be bracing for a fresh wave of unsettled summer weather. According to the Met Office, we’re likely to see a mix of heavy rain, thunderstorms, and sudden drops in temperature.

And while the dramatic skies might look impressive from indoors, getting caught in a storm behind the wheel is a very different story. Between poor visibility, surface water, gusty winds and lightning overhead, driving during a thunderstorm can be seriously dangerous if you’re not prepared.

The good news is that a few simple tips can help you stay safe, stay in control, and avoid unnecessary risk, whatever the weather throws your way.

1. Check the UK thunderstorm weather warning and prep

If a thunderstorm is on the forecast, the safest choice is usually just to delay your trip. If you can’t avoid making the trip, preparation is your best friend. Check the latest weather updates before you set off, and make sure your car is ready to handle rough conditions. That means:

Plan your route and avoid low-lying or flood-prone roads. If you’ve got a sat nav or route planner, now’s the time to use it. Stick to main roads where possible, as they’re more likely to be gritted, drained, and better lit. Pay extra attention to your tyres – if they have low tread, it might be worth 

 before making any long journeys in the rain.

Rain and surface water can reduce tyre grip, resulting in longer stopping distances and a greater risk of skidding. This is also known as “hydroplaning” and can cause serious accidents in wet weather. 

So, how do you avoid hydroplaning? The same way you would during any wet weather: Slow down to give yourself more time to react and keep your distance – ideally, double the usual space between you and the car in front. In storms, a wider gap could mean the difference between stopping safely and rear-ending someone. 

Bonus tip: Cruise control is not your friend during a storm. If there is standing water on the road, you want to be in command of your speed and braking, so stay away from cruise control. 

3. Make sure you can see (and other people can see you)

When the rain's beating down, visibility drops fast, so switch on your headlights – not full beam, you don’t want to dazzle other drivers – low or dipped beams are your best bet. If things are especially bad, fog lights can help you see and be seen, but don’t forget to turn them off if visibility starts to improve.

Your windscreen wipers should also be up for the job. If they’ve been squeaking, smearing, or skipping, make sure you’ve replaced them before driving out in a storm. 

 might be inconvenient, but poor visibility through a rain-streaked windscreen is a disaster waiting to happen.

are visible to other drivers, and that you’re signalling your intentions – especially on the motorway. Use your indicators early and give everyone around you time to react if you’re slowing down, changing lanes, or turning off. In other words: don’t leave people guessing.

4. Know when to pull over and wait it out

If a storm gets too intense (we’re talking strong winds, blinding rain, and lightning overhead), it’s time to put a pause on the journey.

Find a safe spot to pull over, like a lay-by or service area, and turn off your engine. Stay in the car with your windows up, headlights off or on low beam, and wait for the worst to pass. 

Avoid stopping under trees or bridges. They might look like potential shelter, but they can instantly become high-risk zones during storms. Trees can be struck by lightning, causing branches to fall without warning. Bridges and underpasses might bring some protection from rain, but they can also become wind tunnels or flood traps in extreme weather.

Bottom line: what looks like shelter can be a hotspot for unexpected storm damage. You’re much safer in an open area where you’re not at risk from falling debris, water build-up, or any electrical hazards.

5. Your car is your best lightning shelter

Here’s some good news: if you’re caught in a lightning storm, your car is actually one of the safest places to be. That’s because it directs the lightning around the outside of the vehicle and safely into the ground.

It’s only safe to drive in a thunderstorm if you’re prepared and know the risks. Storms bring poor visibility, reduced road grip, and unpredictable winds, all of which make accidents more likely.

If conditions get too severe, don’t push on. Pull over somewhere safe, stay inside the car with windows closed, and wait for the storm to pass. Your car is one of the safest places to be in lightning – just not necessarily while it’s moving. 

If the worst happens and your car needs repairs after the downpour, don’t let a big upfront bill add more stress. With Bumper’s 

, you can split the cost into interest-free monthly instalments, so you stay in control of your budget. We’ve partnered with 5,000+ trustworthy garages across the UK, and applying online is easier than ever – 

The 30/30 rule is a simple way to stay safe during thunderstorms. It goes like this:

This rule helps reduce your risk of being struck by lightning, especially during fast-moving UK summer storms. If you’re driving and hear thunder within that 30-second window, stay inside your car as it acts as a protective barrier against lightning. 

While you can’t stop lightning from striking, you can reduce your risk while driving in a storm: 

Top 5 tips for driving in a thunderstorm

Ever wondered what you might do in a zombie apocalypse? Run for the hills? Stay and fight? Go to the Winchester for a pint and wait for it all to blow over?

Whatever your plan, one thing is for certain: you'll need some wheels to get you out of there – before the horde approaches!

To help you prepare, we've come up with some ideas of what you might face when you visit the dealer to select a new motor. Good luck!

Alastair Shephard

Content Writer