Premium cars with common reliability problems: Audi, BMW, Mercedes and more

As new research reveals common issues on some of the UK’s best-loved motors, we look at eight premium cars with a surprisingly high number of faults.

Some of the most trusted car brands such as BMW and Audi have ‘unacceptably’ high fault rates on their premium models, according to new research from Which?

The consumer group surveyed 50,323 drivers about their 59,921 vehicles in order to identify the makes and models with above-average rates of particular faults.

The researchers then compared these findings against other vehicles of a similar age, as well as asking the manufacturers for comment.

Here are the eight makes and models identified by the researchers as having an ‘unacceptable’ number of issues.

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Alpine A110 (2018-)

Fuel system fault rate: 35% (4% industry average in this age range)

Exhaust/emission fault rate: 16% (3% industry average in this age range)

Cooling system fault rate: 16% (3% industry average in this age range)

As you can see from the figures above, owners reported several recurring faults with the A110, which is Alpine’s only model.

In fact, more than one in three claimed to have experienced serious issues with fuel system components.

Motorists told the researchers that their cars frequently broke down, failed to start or experienced other issues that made them unsafe to drive.

Alpine’s (which is part of Renault) response

“As a part of its quality policy, Renault Group deploys Recall or Service Campaigns as often as necessary to ensure customers complete peace of mind with their vehicle.

“In regards to fuel system faults, we confirm that a service campaign was implemented in December 2023, with more than 50% of cars now rectified.”

Audi A1 (2010-2018)

Fuel system fault rate: 18% (4% industry average in this age range)

Almost 20% of drivers of first-generation Audi A1 vehicles claimed to have had serious issues with their fuel system components.

On top of this, a quarter of respondents told researchers that the problems left them without a car, while 40% had experienced a breakdown because of the fault.

Audi A3 (2012-20)

Fuel system fault rate: 18% (4-5% industry average in this age range)

According to the findings, more than three in five A3 Sportback models aged 0-4 had been left undriveable because of faults with their fuel system components, with 39% breaking down as a result.

However, the picture is less worrying for those with older diesel models as 35% of these drivers reported their cars could still be driven safely despite the fault.

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Audi A3 Saloon (2020-)

Fuel system fault rate: 25% (4% industry average in this age range)

Frustratingly for Audi drivers, this is the third of the brand’s models to make the list.

Some 25% of A3 Saloon drivers who took part in the research claimed their vehicle had been hit by fuel system problems.

Half of owners who experienced this fault reported that their car wasn’t safe to drive, while other vehicles failed to start following a breakdown.

Audi declined to comment when approached by Which? about the research.

BMW 1 Series (2019-)

Exhaust/emission control fault rate: 16% (5% industry average in this age range)

Several BMWs are hit by faults relating to the emission or exhaust, which includes newer versions of the BMW 1 Series.

According to the findings, the fault impacts more than three times as many cars of this type as other diesels in this age range.

A third of owners participating in the survey said that the fault made their car unsafe to drive.

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BMW 5 Series Saloon (2017-23)

Exhaust/emission control fault rate: 16% (5% industry average in this age range)

According to the research, older versions of this model have a fairly high occurrence of faults with their emission and exhaust components.

Despite this, more than half were reported to be safe to drive.

When Which? contacted BMW, the company said it did not have enough information to comment on specific faults.

Mercedes-Benz C Class Estate (2014-21)

Exhaust/emission control fault rate: 17% (5% industry average in this age range)

Although early versions of the Mercedes-Benz C Class Estate experience relatively high numbers of this type of problem, some 85% of those affected are still deemed roadworthy.

When Which? contacted Mercedes, the company said it did not have enough information to comment on specific faults.

Volkswagen Tiguan (2008-16)

Suspension component faults: 22% (4% industry average in this age range)

Suspension springs: 13% (3% industry average in this age range)

When surveying drivers of the first-generation Volkswagen Tiguan, the researchers discovered an unusually high number of complaints relating to suspension components and springs.

Most drivers with a spring-related fault said their vehicle was unsafe to drive. With the component fault, 50% of motorists made this claim.

When Which? contacted Volkswagen, the company did not repsond in time to make a comment.

How dependable are the most popular used cars?

We’ve explored the cars with frequent faults, but just how common are issues with second-hand vehicles?

Extended warranty provider Warrantywise has recently scored the top-selling used cars of 2024 in order to determine their reliability.

Data for the most-sold used cars was taken from the Society of Motor Manufacturers & Traders.

As well as being the most-sold used car of the year so far, the Ford Fiesta takes the crown as the most dependable on Warrantywise’s list.

According to the data, the model has a reliability rating of 70 out of 100.

Ratings are based on factors such as numbers of repair requests, car age and mileage when fault develops, and time taken to repair.

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Reliability scores for Britain’s nine most-sold used cars

Ford Fiesta: 70/100
Vauxhall Corsa: 68/100
Volkswagen Golf: 63/100
Ford Focus: 59/100
Vauxhall Astra: 60/100
BMW 3 Series: 65/100
Volkswagen Polo: 69/100
Nissan Qashqai: 57/100
Audi A3: 64/100

Interestingly, the Audi A3 appears in the Which? research on premium cars with common faults but receiv