Used car buying guide: Mazda RX-8

It goes without saying that the cheaper the car, the more careful you should be, and this is no truer of any car than the RX-8. The rotary engine will be expensive to maintain, even if it’s in good nick, and its impressive ability to get through a tank of petrol is secondary only to its unquenchable thirst for oil – a characteristic of all Wankel designs. Mazda reckons the RX-8 will get through 250ml of the black stuff every 1000 miles.

Ignore the recommended service intervals at your peril; the reason there’s such a plethora of seemingly immaculate RX-8s being broken for parts is because the engine’s rotors wear down over time, allowing air and fuel to travel between its combustion chambers, which results in poor efficiency, diminished performance and, eventually, complete failure.

You’ll know a good RX-8 when you see one; most sensible sellers have a compression test professionally carried out before listing their car in the classifieds (you can’t use an ordinary piston compression tester) and it’s likely any horrors will make themselves known on start-up.

The general consensus is that the engine will manage 60,000 miles before it needs some serious attention, so check the odometer reading tallies with past MOT receipts and really give it the beans on your test drive.

An expert’s view

Aimee Bradley, Rotary Revs: “Over the years, and despite the copious amounts of praise that the RX-8 has acquired, engine failures, high fuel consumption and relatively high running costs have given it a ‘problem child’ label, putting off potential owners who are looking at all the boxes of positives it ticks. It goes without saying that not every RX-8 is a bad one. With some knowledge on what to look for, it can be easy to pick up and enjoy an absolute bargain.”

Buyer beware…

■ ENGINE: Rotaries are much more mechanically simple than piston-powered engines, but failure of the RX-8’s unit can be fatal. See that it starts in less than two seconds when hot or cold, check for flat spots under acceleration and listen out for knocks and rattles. And a compression test is essential.

■ SUSPENSION: Failing anti-roll bar linkages will knock over bumps but aren’t prohibitively expensive to replace. A sagging rear is a sign that a spring has corroded and snapped. Early cars were recalled to have faulty front lower arms replaced.

■ STEERING: Notchy steering can usually be attributed to a failing universal joint, but intermittent power steering assistance is caused by a leaking coolant hose dripping on the sensor. If it hasn’t begun to rust, a thorough clean will usually rectify the fault.

■ BRAKES: This generally isn’t a problem area, but if the car has been laid up, check that the single-piston calipers haven’t seized and that the discs aren’t too rusty. Braking components are readily available and not too costly.

■ BODYWORK: Early RX-8s rust, so you’ll struggle to find a clean pre-2006 car. Check that aftermarket bodykits aren’t hiding anything untoward and get up under the wheel arches with a screwdriver. The boot floor and subframe are also well worth a good check for corrosion.

■ ELECTRICS: Electrical gremlins are low down the list of potential worries. Heated leather seats in early cars might only warm up the bolsters, mind, and a faulty coolant level sensor will throw up a dashboard warning light. If the ignition coil hasn’t been replaced, budget for a new one.

■ ALSO WORTH KNOWING: Enthusiasts fret over ‘stationary gear bearing failure’, which necessitates a complete engine rebuild. It happens when oil pressure drops at low revs and the e-shaft is improperly lubricated, and the inbuilt diagnostics programme usually won’t issue a warning until it’s too late. If the engine knocks on startup, drones at idle and clatters at high revs, call a specialist – and quick.

How much to spend

£1000-£1999: 2005/06 cars taken as part-exchange by dealers. Watch out for write-offs.

£2000-£3499: Mostly low-mileage 228bhp cars with good compression and a fresh MOT.

£3500-£4999: Comprehensively specced pre-facelift cars, including a rare 40th Anniversary edition sold with a 12-month warranty.