• All-petrol line-up could be thirsty
• M40i the least frugal option
• Driven carefully you could get close to 40mpg

What are the running costs?

As a sporty roadster, the Z4’s running costs aren’t its main selling factor, but it could turn out to be more economical than you might think.

The best performer in the range is the sDrive20i, with 38.2-40.9mpg achievable according to BMW.

Unsurprisingly it’s the M40i with the lowest claimed fuel economy figures, achieving up to 35.8mpg. If, however, you make the most of its 340hp engine then you’ll see less than 30mpg with ease.

The 20i emits 157-166g/km of CO2, while the M40i produces 179-184g/km, which isn’t too bad considering the power.

Servicing and warranty

For peace of mind, the Z4 comes with BMW’s three-year, unlimited-mileage warranty to keep you covered if things do go wrong.

Service plans can be paid for monthly or up front. They include seasonal health checks, fluid top ups and a wash.

Reliability

• Four recalls for the Z4 so far
• We’ve experienced some tech niggles
• Three-year warranty as standard

BMW has a good reputation for building solid and dependable cars, and there’s little reason to believe the Z4 will buck this trend. The engines are found in several other models and are proven to be trustworthy.

There have been four recalls, ranging from brake discs not being to specification to a problem with the fuel tank weld, to the steering tie rod and the bearing in the crankcase.

We’ve found a couple of issues with the firm’s latest infotainment system too. Like with the BMW 8 Series, it regularly disconnects from the wireless Apple CarPlay connection, which can become tiresome. It could well just be a small issue that a software update would fix.