25 most unreliable cars

While some cars motor along for years without missing a beat, others are afflicted by fault after fault, so here's our round-up of the most problematic 25 cars aged up to five years old...

Most unreliable cars

In our most recent Reliability Survey, held in association with MotorEasy, more than 18,000 people told us how dependable their cars had been over the previous 12 months, with a quarter reporting at least one fault.

To help rate those faults for seriousness, we divided them into 15 categories: air-con, battery, bodywork, brakes, engine, engine electrics, exhaust, fuel system, gearbox/clutch, interior trim, non-engine electrics, sat-nav, steering, suspension and other. The most frequent area where problems were cited was non-engine electrics, with 24% of owners reporting this type of fault. 

We also asked owners to tell us how long their car was off the road while it was getting fixed and how much the repairs cost. While the majority of faults cost £101-£200 to put right, 3% of owners paid more than £1500. 

Combined, this information allowed us to give each of the 218 models (from 31 different brands) featured in the survey a reliability rating. As you'd expect, this penalises cars that have lots of expensive faults and rewards dependable ones that suffer no or only minor faults that are cheap and quick to repair.

Below we count down the least dependable cars aged up to five years old. Or to tell us about your own car, complete our 2020 Reliability Survey.

25 most unreliable cars

25. Audi Q2 (2016 on)

Audi Q2 front - 19 plate

Reliability rating: 82.4%

A fairly high percentage of Audi Q2s had a fault (24%), and although 10% related to non-engine electrics, 7% were more serious, affecting the gearbox/clutch. Most were fixed in less than a week and repaired for free, but some cost £201-£1500.

Read our full Audi Q2 review >>

24. BMW 5 Series (2010-2017)

BMW 5 Series

Reliability rating: 88.4%

The previous-generation BMW 5 Series suffered a fairly high proportion of faults (39%), and some were in serious areas; 10% had exhaust issues and 8% had engine issues. A quarter of cars couldn’t be driven, and although most were fixed for free, a few owners had to shell out up to £1500.

Read our full used BMW 5 Series review >>

Save money on a new BMW 5 Series with What Car? >>

23. Mercedes S-Class (2013 on)

Mercedes S-Class

Reliability rating: 88.1%

Most Mercedes S-Class models were fixed for free, with only a few owners having to pay up to £300. However, around 50% of cars suffered a fault, most commonly with non-engine electrics. All cars could still be driven, and the majority were back on the road in less than a week.

Read our full Mercedes S-Class review >>

22. Mercedes C-Class (2014 on)

Mercedes-Benz C-Class

Reliability rating: 87.6%

Just under a third of Mercedes C-Class models had faults, mostly with the exhaust, then the engine electrics and suspension. Around half were laid up for more than a week and a quarter were rendered undriveable. Most fixes were free, but a few owners paid up to £1000.

Read our full Mercedes C-Class review >>

=20. BMW 1 Series diesel (2011-2019)

BMW 1 Series front - red

Reliability rating: 87.0%

Although previous-generation petrol-engined BMW 1 Series models are pretty durable, 34% of diesels had trouble, mainly with the engine. One in five were undriveable and took more than a week to fix, plus some cost owners up to £500.

Read our full BMW 1 Series review >>

Save money on a new BMW 1 Series with What Car? >>

=20. Peugeot 208 (2012-2019)

Peugeot 208 GTi

Reliability rating: 87.0%

Just over a third (35%) of Peugeot 208s went wrong, with suspension, engine and non-engine electrics the main culprits. However, all cars remained driveable and most work was done under warranty; only a small percentage of customers were presented with bills costing up to £300.

Read our full used Peugeot 208 review >>

Save money on a new Peugeot 208 with What Car? >>

19. Jaguar XF (2007-2015)

Jaguar XF

Reliability rating: 86.8%

Although a fairly high percentage (37%) of Jaguar XFs suffered a fault, all could still be driven and were fixed within a day. However, most weren’t fixed under warranty, costing owners up to £200 each time.

Read our full used Jaguar XF review >>

Save money on a new Jaguar XF with What Car? >>

18. Nissan Pulsar (2014-2018)

Nissan Pulsar

Reliability rating: 86.6%

Almost 40% of Pulsars had a fault, the majority to do with the battery. Nearly half couldn’t be driven, but all their faults were rectified the same day. Three-quarters of work was done under warranty, but a quarter of owners paid bills ranging from £101-£300.

Read our full used Nissan Pulsar review >>

17. Volkswagen T-Roc (2018 on)

Volkswagen T-Roc front

Reliability rating: 86.5%

Only 25% of Volkswagen T-Rocs had a fault; most (13%) concerned bodywork, although there were also issues with the engine and its electrics. All work was done under warranty, but most cars took more than a week to repair.

Read our full Volkswagen T-Roc review >>

16. Seat Ibiza (2008-2017)

Seat Ibiza

Reliability rating: 86.0%

The previous Seat Ibiza isn’t ageing well. More than a quarter were faulty, with non-engine electrics the most troublesome area. A third took more than a week to fix; less than half of the fixes were done under warranty and some cost up to £500.

Read our full used Seat Ibiza review >>

Save money on a new Seat Ibiza with What Car? >>

Tell us how reliable your own car is >>