Best and worst older cars for reliability: sports cars and coupes

How dependable are cars as they get older? Here’s what the owners of sports cars and coupes between five and 20 years of age have told us...

Porsche Boxster front three quarters

Most reliable Porsche Boxster/Cayman (2012-2016)

Reliability rating 94.7%

What went wrong? Air-con 11%, interior trim 6%, non-engine electrics 6%

The previous-generation Boxster and Cayman are ageing well, with only 17% of cars suffering a fault and no major components failing. All cars could still be driven and 75% were put right in a day or less; 75% of work was done for free, with the remaining bills ranging from £501 to £750.

Owner’s view “I’ve owned quite a few Porsches over the years, and this is the best one yet. Build quality and reliability are both excellent.”

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BMW Z4 (2009-2019)

Reliability rating 94.1%

Used BMW Z4 Sports (09 - 17)

Only 17% of previous-generation Z4s went wrong, according to owners, with the engine and nonengine electrics being the only areas affected. All cars remained driveable and all were put right in less than a week; half were back on the road in a day or less. Although no cars were repaired under warranty, bills ranged from £101 to £200.

BMW 4 Series Coupe

Although 20% of the 4 Series models we were told about went wrong, the most common issue was a minor one: interior trim. All cars could still be driven and 75% were repaired in a day or less. A quarter of work was done for free, and those who had to pay received bills ranging from £101 to £300.

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Least reliable Porsche 911 (2004-2011)

Reliability rating 71.9%

What went wrong? Air-con 25%, engine electrics 17%, non-engine electrics 8%

Used Porsche 911 Coupe (05-12)

A third of 911s of this generation went wrong, according to owners, with just over half being rendered undriveable and nearly three-quarters taking up to a week to repair. Although 43% of work was done for free, other owners were left with bills of between £501 and £750. 

Owner’s view “The 911 is expensive to service and I’ve had a couple of pricey bills for faults.” 

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BMW 6 Series Coupé/Convertible (2011-2018)

Reliability rating 73.7%

Used BMW 6 Series 2011-2018

Only 17% of 6 Series owners told us their car had suffered a fault, with the biggest issues being related to non-engine electrics, followed by interior trim and steering. However, half of cars were rendered undriveable and 75% took more than a week to put right. No work was done for free and 50% of repair bills exceeded £1500.


Porsche Boxster/Cayman (2004-2012)

Reliability rating 86.5%

Porsche Cayman front three quarters

Despite their presence here, the second-generation Boxster and Cayman are pretty dependable, with only 18% of owners reporting faults. Problems were split evenly between the air-con, battery, fuel system, gearbox/clutch and non-engine electrics. Nearly two-thirds of cars could still be driven and were fixed swiftly. One in five faults was remedied for free, but some cost £501 to £1500 or more to fix.

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