Joseph Law

Bumper Content Writer

Joseph Law | Author

Alastair Shephard

Content Writer

Alastair Shephard | Author

Tesla remains one of the most popular EV brands sold in the UK. In this article, we’ll take a look at how reliable they are and how their most popular models rank compared to other cars.

In a recent What Car? reliability survey, the Model 3 placed 9 out of 20 cars. This might make you think the Model 3 is unreliable, but EV’s in general are proving to be more reliable than ICE (internal combustion engine) cars, thanks to their relative simplicity. 

The Model Y, Tesla’s most popular model, fares even better in reliability scores, regularly placing highly in the reliability charts. Discover our full 

There are 4 different Tesla models you can get in the UK. If you’re considering one but want to make sure it’s reliable, here's a full rundown. 

Are Teslas more reliable than petrol or diesel cars?

When comparing the reliability of Tesla’s most popular models (the Model Y, 3 and S), to the average internal combustion engine car, the electric vehicles almost always come out on top.

This is despite the numerous Tesla build quality issues talked about in the motoring world, but thanks to their simplicity, almost all EVs tend to be more reliable than their equivalent petrol or diesel cars.

Like all cars, Teslas come with their fair share of common faults, some due to design issues, some to manufacturing, and some to software. Because Tesla shares a lot of parts and designs between models, some issues affect more than one car:

Is Tesla ownership different to traditional cars?

With over-the-air (OTA) diagnostics and servicing, Tesla set out to revolutionise the dealer-customer experience, and they mostly succeeded, with many other manufacturers now following suit.

Own a Tesla, and you are likely to be pleasantly surprised when a new feature suddenly appears on your dashboard. 

With the cars already being crammed full of tech like powerful processors, large screens and multiple sensors, adding a new driving or infotainment feature is entirely possible, without the car needing to leave your driveway. 

Recent features added to existing Tesla cars:

With the cars able to connect wirelessly to Tesla’s servers, any issues can immediately be looked into by a diagnostic tech. Drivers can also call any of the many service centres to check out unusual behaviour or faults they have noticed. 

This is in stark contrast to vehicles of the past, where drivers had to take them to a pre-booked and costly garage for diagnostic and repair.

Mobile mechanics have been around for decades, but Tesla 

run mobile service vehicles they call the Mobile Rangers. 

These can be booked through the app, to change things like low voltage batteries, bulbs and other minor repairs. 

The way Tesla manages to offer such a customer-focused service is that they do not operate franchised dealerships, like almost every other manufacturer. 

The dealership is owned by the company themselves, allowing better control over stock movements, price changes and vehicle updates. 

It also means they can offer a competitive warranty, Tesla service centres are known for generally being good with paying out for repairs.

If you have an older Tesla that is out of warranty, another type of EV, or even a petrol or diesel car, Bumper can help with zero-interest car repair financing. 

, and spread out your car repair costs into manageable monthly installments.

How reliable are Teslas? (Buyer's guide 2026)

Are Teslas Reliable?

The thermostat in your car’s engine is a small but vital component. It regulates the engine's temperature by allowing coolant to flow into the radiator when needed. Thermostat issues can be worrying because they can often mimic a blown head gasket. 

Thankfully, thermostats are a relatively cheap problem to fix, but can easily develop into something worse if left unattended. In this article, we’ll take a look at how much thermostat issues cost to repair, how to detect them, and when you should get them fixed.

How much does it cost to replace your engine's thermostat?

Like all car repair costs, thermostat replacement can vary depending on the type of car and what type of garage you take it to. 

What are the symptoms of a failing engine thermostat?

A broken or sticking thermostat produces some tell-tale symptoms:

How to tell a broken thermostat from a head gasket issue

The symptoms of a broken thermostat can be similar to those of a damaged head gasket, so it’s important to take note of all the symptoms before worrying too much.

A failing head gasket is usually accompanied by one or more of the following, whereas a faulty thermostat would not:

A good test to do to rule out a head gasket issue is a block or combustion leak test. This cheap kit uses a special liquid that changes colour when it comes in contact with exhaust gases. 

In general, a thermostat is a device that regulates the temperature of a system, be that inside a room, or in this case, of an engine. They are in effect, a heat-controlled valve, allowing coolant to flow through the radiator.

The radiator removes heat from the coolant, in turn cooling the engine. If the thermostat sticks closed, the engine will not be able to shed the excess heat. If it sticks open the coolant will constantly flow through the radiator, preventing the engine from reaching operating temperature. 

Up until recently, most cars’ thermostats were entirely mechanical, using a piece of expanding and contracting wax, to open the valve. In many modern cars though an electronic thermostat is used, which allows more precise control.

How important is repairing an engine’s thermostat?

Despite the thermostat being a small and relatively inexpensive part, its role is crucial to the health of the engine. An engine with a stuck-open thermostat will perform inefficiently and eventually run poorly. 

An engine with a thermostat that is sticking in the closed position is on borrowed time. Without adequate cooling, the engine can easily overheat. If this goes unnoticed, the engine heat can do serious damage, such as warping heads and cracking engine blocks.

Whether your car's issue is the result of a stuck thermostat or something far worse, Bumper can help with the cost. Rather than paying up front, Bumper’s interest-free 

 allows you to split the cost of repairs into monthly payments. Apply online or at the garage or dealership.

How much does it cost to replace a car thermostat? (2026)

Thermostat Replacement Cost

Timing chain replacements can cost anywhere from £900 to £2,000 in the UK. That’s around twice as much as most timing belt replacements. In this article, we’ll discuss what factors affect the timing chain replacement cost and why they cost so much more than a belt to replace.

How much does it cost to replace a timing chain?

On average, a timing chain is likely to cost between £800 and £1400 to replace, but this can vary greatly depending on the make and model of the car and where you take it to have the work done.

With premium marques, such as BMW, Mercedes and Audi, expect the upper end of the above range.

Economy cars, such as those made by Ford, Toyota, Vauxhall, etc, are usually less, mainly through lower parts prices and less complexity, averaging around £1,200 in 2026.

What affects the timing chain replacement cost?

Like any vehicle repair, there are numerous factors that affect the cost of replacing a timing chain in a vehicle, including the complexity of the engine, parts availability and cost, and labour rates.

Certain engines, such as the Volkswagen Audi Group Diesel 3.0 V6, have the timing chain at the back of the engine, meaning the whole engine needs to be removed to complete the job. Others, particularly performance cars, also need the engine removed, as the space under the bonnet is so limited.

The type of garage you take the car to also has a massive impact on price; independent garages are typically cheaper than the main dealer.

Why is a timing chain so much more expensive to replace?

In years gone by, an engine having a timing chain was almost always preferable, but there is a growing list of cars that have timing chains that are known to be problematic:

This engine powered many different BMW models from 2007 to 2014, such as the 3 series, 2 series, 5 series, X1, X3 and others. Basically, any 1.6, 2.0 or 3.0 diesel engine in a car made between 2007 and 2015 may be affected. 

This otherwise great engine was marred by poor timing chain reliability, with many cars needing new chains and tensioners if caught in time, and others needing new engines. 

The fault is thought to be a combination of an issue with the sprocket design, chains stretching prematurely, and tensioners not being reliable.

Land Rover 2.0 Ingenium Engine (2015 - 2019)

A common fault with JLR’s (Jaguar Land Rover) 2.0 diesel engine is well known in the industry. The most common cause of failure is the plastic chain guides that wear down and break, causing both a loose chain and debris in the oil. 

The problem is so systemic that a number of class action lawsuits have been filed across the world, Jaguar issues various changes to the engine in 2019, that helped with some of the issues, but timing chain problems are still not uncommon.

In cars with known timing chain issues, such as those listed above, general advice suggests replacing around 100,000 miles at most. The best way to check is to consult a local independent specialist.

Unlike servicing, or even timing belts, cam chains usually have a lifespan set by the manufacturer. This is because they’re usually considered to last the life of the engine, many owners of the cars mentioned above will attest to the contrary, though!

Because there are often no set replacement intervals, it’s important to keep an eye (and ear) out for the following symptoms of a worn timing chain on your car:

What happens if you ignore a worn timing chain?

Timing chain replacement is expensive, but it is far cheaper than the alternative; replacing an entire engine - which is what is likely to be required if your timing chain snaps or jumps. 

Once the timing chain starts to stretch, the guides or tensioners wear, or you notice any of the symptoms above, some amount of damage is already done, and continuing to use the car will only exacerbate it. 

For this reason, it’s important to get your car checked out as soon as possible, especially if it’s a model known to have timing chain issues. 

Bumper can help with timing chain replacement

If your car is making a suspicious noise that sounds like timing chain wear, or needs any other repair work done, Bumper's interest-free car repair finance can help. Split the cost of repair and maintenance into monthly instalments with no added costs. Apply online and choose from thousands of garages and dealerships.

How much does a timing chain replacement cost? (2026)

Timing Chain Replacement Cost

All modern cars will have either a MAP sensor or a MAF sensor, and some have both. MAP (Manifold Absolute Pressure) sensors measure the pressure of the air entering the engine. MAF (Mass Airflow) sensors or meters measure the amount of air entering the intake manifold. 

Both are needed to ensure smooth and efficient operation of the engine, allowing the ECU to make minute adjustments to the amount of fuel injected to keep a perfect fuel to air ratio.

How much does it cost to replace a MAF or MAP sensor?

Replacing a MAF or MAP sensor typically costs between £190 and £400, depending on the make, model and age of the car, and what garage you take it to.

Cars such as performance cars and luxury ones with large, complex engines can cost even more than this if the part is particularly difficult to access. 

In some cases, your mechanic may suggest simply cleaning the sensor first, which will cost less. However, there will still be labour charges. Typically, this can be completed in one or two hours at a cost of around £70 to £250.

Can cleaning the MAF/MAP sensor help fix the issue?

Yes, it’s usually worth cleaning the MAP or MAF sensor before replacing, especially if diagnostic checks show the sensor is working but not correctly. 

Because MAP and MAF sensors sit in the intake air stream, they can become clogged with dirt, pollen, and even oil or soot, especially if your car is fitted with an EGR system. 

Modern engines use an electronic control unit (ECU) to accurately and continually monitor the engines’ performance and efficiency. 

It does this by utilising numerous sensors that measure the incoming air and outgoing exhaust gases, both their volume (MAP/MAF sensors) and chemical composition (oxygen sensor). 

Without adequate information, for example, when a sensor is faulty or giving erroneous readings, the ECU can have trouble monitoring the engine's performance, which leads to poor running.

Because they read similar things, the symptoms of a faulty MAF or MAP sensor are usually very similar. They include:

Yes, in most cases a MAP or MAF sensor that is not reading correctly, will cause an engine warning light to illuminate, this will cause the car to fail an MOT.

Even if your engine management light is not illuminated, the engine is very likely to be producing higher than normal emissions readings, which could be enough to fail an MOT.

Can I drive with a faulty MAP or MAF sensor?

It’s unlikely that a MAF or MAP sensor will render the car completely undriveable, but it could well cause it go into limp mode, which can be extremely dangerous depending on when it happens, for instance on a motorway or at a busy junction. 

For this reason it's always recommended to get the issue fixed as soon as possible.

 on anything from MAP sensor replacements, to wheel refurbishments, to engine rebuilds. Apply online and choosen from 1,000s of trusted garages and dealerships across the country.

How much does it cost to replace a MAP or MAF Sensor? (UK 2026)

MAP and MAF Sensor Replacement Cost

The Audi A4 is a midsize saloon or estate, popular for its spacious cargo space, luxurious interior and premium build quality. However, premium brands such as Audi are often more expensive to repair, thanks to higher parts and labour costs. 

In this article, we’ll take a look at how much it’s likely to cost to repair cooling issues on your Audi A4, including parts, labour and ongoing costs.

How much does it cost to repair the cooling system on an Audi A4?

Depending on the exact issue, repairing cooling issues on an Audi can cost between £30 and £1,000+. Other factors include what type of mechanic you take the car to and what engine it has.

As a car’s coolant system is very complex, the potential costs can range greatly, from under £30 for a new expansion tank cap to major engine work.

In some cases, a faulty coolant expansion tank cap can allow the normally pressurised system to boil over and lose coolant. A new cap can be bought for as little as £30 and fitted yourself, without any tools needed. 

A coolant leak from a damaged hose, radiator or fitting can cost between £100 and £500 to repair. On the top end of the scale, major issues such as a leaking water pump, head gasket failure or worse, can easily cost over £1,000 or more to fix properly.

In some cases, something like a cooling fan may not be working due to either wear or an electrical fault. Repairs of this nature will typically incur time for diagnostics and repair, generally costing around £150 - £300, depending on the fault.

What type of coolant does an Audi A4 use?

Audi A4s generally use a variation of G12 or G13 coolant, which is usually a purple/pink colour, but be sure to check your owner's manual to confirm before buying or using. 

This type of coolant is specifically designed for engines that have aluminium components, as certain chemicals are not recommended for use in contact with aluminium and can cause damage. 

How much does coolant for an Audi A4 cost?

Typically, G12 or G13 coolant can be bought for around £6-£10 per litre, in ready-to-use form. Most Audi A4 models will take between 5 and 10 litres to fill the system. 

It’s often cheaper to buy concentrate, though, and mix it yourself, providing you read the dilution instructions correctly.

Car cooling systems use a closed system of liquid coolant to move heat from the engine to the radiator, where it is dissipated by incoming cool air. This is achieved by an engine-driven water pump, and a system of hoses. 

An efficient cooling system is needed because engines create a lot of heat when running, and overheating can cause serious damage to major components.

If your radiator is damaged, be it through age or damage from road debris, it can easily cause a coolant leak. However, in most cases, it is a better option to buy a new radiator than pay for a repair to be made. 

This is because replacement radiators are generally less than £100 for a non-genuine part, one exception potentially being if the car is a rare or high performance model, where parts are hard to find.

Can you drive with a damaged cooling system?

If your cooling system is not working effectively, either because of a leak, an ineffective radiator, or a broken radiator fan, or something else, you should avoid using the car completely. This is because even a short journey can cause the engine to overheat.

Running an overheating engine, even for less than a minute, can cause permanent damage to the head or engine block, both costing thousands to repair. 

If your car has a coolant issue, or any other problem likely to present big bills, consider Bumper’s 

Bumper helps you spread the cost into manageable monthly payments. Apply online and choose your trusted repairer today.

How much does it cost to repair a cooling system on an Audi A4?

Audi A4 Cooling System Repair Cost

Turbochargers serve an important role in modern cars, increasing fuel efficiency and power output. But they are complex components that can cost anywhere from £700 to £2,500+ to replace if they go wrong.

In this article, we’ll take a look at what a turbo is, how much it costs to replace if it's beyond repair, ways you can save money on replacing a turbo, and how you can extend its lifespan.

How much does it cost to replace a turbocharger?

Turbo replacement costs can vary greatly depending on the type and model of car. The table below shows some indicative prices for both reconditioned and new turbos:

Are reconditioned turbochargers worth it?

Reconditioned turbochargers are a popular choice for those looking to save some money. To know whether it’s worth fitting one to your car, consider your budget, the price difference between new and refurbished, and the age or value of the car. 

It’s important to remember that reconditioned parts are not the same as used parts; a reconditioned turbocharger will typically come with the same level of warranty/guarantee as a new one.

During the reconditioning process, parts that commonly cause turbo failure are replaced, including the seals, bearings and actuator.

Turbochargers are fitted to cars to increase the engine's performance and fuel efficiency. They do this by using waste energy from the exhaust gases to compress the air entering the engine. 

To achieve this, a turbine extracts energy from the exhaust gases and spins a compressor on the same shaft. A typical car turbo will spin at anything from 100,00 to 300,000 RPM.

Cars with known turbocharger issues in the UK

There are a few car or engine models in the UK that are known for having turbo issues. If you’re looking into buying a new car, be sure to check for evidence of these problems:

There are numerous reasons why a turbo can fail, despite many modern turbo units being made of high-performance metals and using ceramic bearings:

If your mechanic has told you your turbo needs replacing, or you suspect something is wrong with it, it’s highly advisable to at least get the problem properly inspected before continuing to drive the car. 

This is because a failing turbo can cause more engine damage. The best-case scenario is that your engine will use more fuel, have worse emissions and even burn engine oil – but it's best to get it checked.

If your car needs expensive repair work, such as a turbo replacement, Bumper can help spread out the cost into more manageable monthly payments with 

. Apply online and choose from 1000s of reliable repairers.

How much does it cost to replace a turbocharger? (UK 2026)

Turbocharger replacement cost

You don’t need to be an expert mechanic to know that a bad fuel pump is going to hinder your car from working properly, but when it can cost between £400 and £1,300 to repair, it’s good to brush up on how they work and what is involved in replacing one. 

In this guide, we’ll cover both in-tank and high-pressure fuel pump costs, including ways you can save money on a replacement – and how to tell if your pump is on its last legs.

There are two different types of fuel pumps in most cars. The type your car has can affect the cost of the replacement. Another factor is the type of fuel your car uses:

What affects the cost of replacing a fuel pump?

Like any vehicle repair, there are multiple factors at play that determine the cost of replacing a fuel pump:

Cars generally have two fuel pumps, one in the tank that brings large volumes of fuel to the engine, and a high-pressure pump in the engine bay that provides the extremely high pressure needed for fuel injection. 

The in-tank pump is a relatively simple, electronic pump that can be changed for around £200 in some cars. It usually requires either the removal of the rear seats or the dropping of the fuel tank from the car to access. 

Often, the high-pressure pump is attached to the side of the engine and is driven mechanically by a camshaft or other rotating component. This pump creates the pressure necessary to atomise the fuel when it is injected. 

In some cases, high-pressure fuel pumps are easier to access than the in-tank ones, but they are almost always more expensive parts to buy replacements for.

Diesel engines need extremely high pressure fuel injection to run, in the region of 20,000 - 40,000 PSI, that’s around 500x more pressure than in your car’s tyres! 

Because of this, diesel fuel pumps can cost significantly more to replace than petrol ones, as the pump is a more costly part to buy. This is the case with the on-engine high pressure pump at least, in-tank ones are around the same cost as petrol cars.

High pressure pumps can often be repaired or reconditioned, meaning you can usually buy reconditioned fuel pumps to suit your vehicle.

Whilst some garages may have concerns fitting a reconditioned fuel pump, for fear of it not lasting as long as an OEM part, they do usually come with 1-2 year guarantees. 

Main dealer garages usually charge a lot more than independents. They are also not likely to be willing to fit non-OEM parts. That said, with some modern cars, the dealer is the only option thanks to the complex diagnostic tools needed. 

Because the fuel pump is so crucial to the engine running well, symptoms are usually un-misable:

It’s not recommended to continue driving your car if it has a fuelling issue, especially as the problem could easily get worse at any point, potentially leaving you stranded. 

Not only that, the inconsistent nature of the issue could well prove to be very dangerous, if the car cuts out or hesitates whilst on a motorway, or large roundabout.

Get your car back on the road without the big upfront bills with Bumper’s zero-interest 

. Choose from hundreds of nationwide approved garages, and spread out the cost into manageable chunks. 

How much does a fuel pump replacement cost? 2026

Fuel pump replacement cost

New analysis has revealed that potholes are responsible for up to 1.7 million MOT failures every year – a figure that will come as little surprise to anyone who regularly navigates Britain's crumbling roads. 

Using DVSA data, The Sun analysed 2.5 million MOT failure points typically associated with pothole damage across 1.74 million cars. 

Over 1.1 million suspension arms and ball joints were found to be damaged, 882,000 springs had snapped, and 450,000 shock absorbers were ruined.  

Two-thirds of all these failures were concentrated in the front wheels – the first point of contact when a car drops into a ditch.  

However, not all failures will have been caused solely by potholes. Natural wear and tear may have also played a role in the MOT failure. 

Birmingham topped the list of pothole damage hotspots, with 34,758 cars failing their MOT with faults commonly linked to road surface damage. Sheffield came second with 33,896 failures, followed by Nottingham, Glasgow and Cardiff. 

Until the roads improve, the best defence is knowing how to drive around the problem. 

Advice