Shed of the Week | Mazda RX-8


Anybody know what the word Renesis means? It's written on the top of the engine cover of Mazda RX-8s.

If there is an answer to this, it's quite well hidden by the internet. Shed's best guess is that it's a mashup of genesis (the Biblical startup event rather than the public schoolboy band), with an R at the front signifying rotary. Whatever the accuracy of that theory may be, Renesis meant a change to a Multi-Side Port exhaust system, boosting power and reducing fuel consumption and emissions relative to the company's earlier peripherally-ported rotaries.

All of which was great for Mazda, but for customers Renesis still meant trouble. Mazda knew that at the time, too. Shed remembers testing one of the first UK RX-8s and being somewhat flummoxed by the sight of a large flagon of oil in the boot and a plea from Mazda UK's press department to for god's sake please check the oil level on every petrol fill thank you very much.


Thing is though, if you can put up with the high running costs honestly pointed out in the ad by the vendor - 20mpg in vaguely sporting use and a scary top-level tax rate of Β£570 a year - the RX-8 is an absolute jewel. Producing up to 228hp from 1.3 litres - although the twin-rotor motor was regarded as a 2.6-litre for the purposes of receiving 'best engine' awards, something it did on a pretty regular basis - the spinny rather than up-and-down-bangy nature of the engine gave it an insatiable appetite for revs. So much so that Mazda had to fit a warning buzzer to remind folk that even their engineering brilliance had limits.

But how do you fend off the well documented gen-one RX-8 evil of poor or non-existent hot starting caused by a lack of compression when the rotor apex seals wear out for want of adequate lubrication? The vendor's own solution, and one that a few RX-8 owners have copped on to, has been to chuck a dod of two-stroke oil into the petrol tank every couple of fills to give the car's own oil metering pump injectors a helping hand in keeping the rotor apex seals healthy. This remedy is also thought to soften the carbon buildup that can happen if you chug around at low rpm all the time. Smart owners know that 'a redline a day keeps the carbon away'. Stuff called Sea Foam is also popular for de-carboning but probably not if your car still has a cat.

Some do say that if the OMP is working (which it doesn't always do - they have a reputation for failing at around 80,000 miles) you shouldn't need to go down this route, but if you use your RX-8 hard or you have a goodly mileage on the clock then Lambretta/Fizzie style premixing won't do any harm and may even be a good idea. Around 100-125ml a tankful is thought to be about right. Much more than that and your car will start to smell like a chainsaw.


Our 2007 Shed is from the back end of the gen-one Eights. A 2008 refresh braced up the suspension, but even in unbraced gen-one form the RX-8's double-wishbone front, multi-link rear chassis needed no handling warnings. Minus fluids and ancillaries, the engine weighed less than 115kg, a ridiculously small amount sitting well back in the car. In combination with the rear-wheel drive allowed the suspension to be set up to provide a measure of lightfooted delicacy. The Bilstein-suspended R3 model of 2009, which Shed also tested, was not far short of wonderful.

This particular RX-8 lived a very quiet life for its first three years, accumulating fewer than 12,000 miles in that time. Having passed the MOT in June 2010, it was given another test two months later, possibly to ease the progress of a sale to a nervous buyer. More conventional (but still low) annual mileages followed for the next four years, at which point the usage dropped back down again. Just 12,000 miles have been covered in the last five years.

Now that it stands at 54,000, what problems might its next owner expect? Well, nothing to do with cambelts, valves, lifters, or even conventional crankshafts for a start, because it doesn't have any of those. Early RX-8 problems associated with the suspension, fuel tank leakage and exploding steering wheel airbags (eek) were sorted on recall, or should have been anyway. Fogging and condensation in the lights at either end are down to poor quality gaskets. The central armrest lid is famed for losing its ability to latch shut, the sun-visors fall apart and the gen-one starter motor is pants. It can and should be cheaply replaced by an aftermarket item. The catalytic converters don't last that long. Poor performance or a 'check engine' light might be malfunctioning oxygen sensors, but can just as easily be down to the cat. Premix can hasten a cat's demise, but decat systems are of course available.


For possibly the first time, unfavourable yen exchange rates came in quite handy for a car manufacturer in that they provided Mazda with an extra excuse for binning the RX-8 (on top of it failing Euro 5) in the summer of 2011, two years after an extra oil injection port has been added to lift the lubrication injector count to six. The last European RX-8s were sold a year earlier, in 2010.

Today, in 2019, it's well-nigh impossible to pay more than Β£7k for an RX-8, and more often than not you'll pay considerably less. Like here, where the bill will be Β£1,450. If you've never tried one, you really should, especially at this low-risk level.

Which brings us back to the beginning, or the genesis, of this story. Mrs Shed likes a spot of Genesis. Her favourite track is In Too Deep, but whenever she is feeling flirty enough to pop that onto the Dansette, Shed quickly reaches for his own well-used copy of Invisible Touch. At which point he usually becomes a Man On The Corner, in a Land Of Confusion.


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Comments (102) Join the discussion on the forum

  • kainedog 01 Nov 2019

    I like the looks , quirkiness but the reliability , thirst and suspiciously cheapness puts me off. Ls swapped examples make sense

  • the_hood 01 Nov 2019

    Still looks good but unreliability, low mpg and high tax would put me off.

    Edited by the_hood on Friday 1st November 06:11

  • shortar53 01 Nov 2019

    Had one. In this exact colour in fact.

    Best car I've ever driven... But ruinously expensive, 200 miles on a tank of petrol, 240 on a run.
    Took a slight bump to the passenger side exiting a mini roundabout when the geriatric turning left decided it was a T-junction and he had right of way, it was never the same afterwards, the engine gave out not long after I'd part exchanged it.

  • GTEYE 01 Nov 2019

    Some cars are cheap for a reason. This is one. Run it until it breaks, then throw it away. Or just avoid.

  • Cambs_Stuart 01 Nov 2019

    I know abput the appaling fuel consumption, frail engine, appetite for expensive consumables (like coil packs and leads) but i still want one.
    They sound fantastic, the rear doors are cool and apparently they're nice to drive too.

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