The Mazda engine which you should double check!

The term unreliable isn't too often found in a sentence with Mazda due to the fact that the in question Japanese car manufacturer is knowing pretty well what he's doing while most of its creations, except the Wankel maybe, turned out to be reliable and easy to live with even in log terms but it seems like that even a such good reputation having car company as Mazda can make mistakes and the 2.2 SkyActive-D diesel is no exception.

To get a clear image of the main issues which are related to the SkyActive-D we first have to look at its structure and operation for further understanding it. Mazda decided to lower the compression ratio of the in question diesel from 16.3 to 14.0 just because by applying this method less nitrogen oxide is leaving the exhaust due to the fact the temperature of the combustion is lower in this case. This improved efficiency and more environmentally friendly character might helped in getting greener but it carried over some drawback which are highly affecting the operation if this engine. The problem with a lower compression is that it's leading to less pressure and a dropped temperature in the combustion chamber, resulting a worse air fuel mixture, harder self ignition at cold starts and a less effective warmup. To eliminate these issues ceramic coated glow plugs were introduced which are pre heating the air in the combustion chamber while the exhaust valves open during the intake stroke, letting hot gasses penetrate back into the mentioned area. In real life condition if we're adding up all these phases which are occurring inside the SkyActive-D then the result is an even faster carbon build up compared to other modern turbo diesel engines, meaning that if isn't used constantly above 80 km/h (50 mph) when the regeneration of the diesel particulate filter (DPF) is engaged, than the engine will clog because of the built up carbon. Driving the in question diesel in the city environment is nearly impossible without bumping into this issue because this 2.2 L unit is only operational on the highway when the travelling speed is above the earlier mentioned speed otherwise fuel consumption will increase which is related to the regenerative cycle of the engine when the fuel injectors are injecting fuel in the DPF just to burn the deposited carbon out, a phase which if it's ignored overtime than fuel will get back to the crankshaft, mixing with oil, the EGR valve and turbo will clog or the engine won't be able to operate. Now lets mention the dual stage turbocharger which is standard in the SkyActive-D; integrating a small and a big turbocharger in a single housing is a more compact way than having two separate ones but in this case the turbo diversion valve which is switching between the small and the big turbo brakes often, leading to the replacement of the entire dual stage turbo because it can't be repaired for some reason. Than there was the extended 20000 km oil change period - which than was changed to flexibe one - which if it was applied than the timing chain of the oil pump should be replaced at 120000 km, otherwise this timing chain will get loose damaging the engine.

So, if Mazda's 2.2 SkyActive-D is coming standard with so many issues then how comes that it isn't found in one of the "Choose Wisely!" articles of this blog in which people are warn not to buy a such engine powered vehicle? The answer is simple, there was a recall for the SkyActive-D and Mazda was constantly updating it since it deputed in 2012, meaning if you're avoiding the first generation of this engine family and go for an after 2018 version were most of these problems were solved than you can get a quite, smooth, eco friendly and great millage powered Mazda without all this "package" while even if you're choosing an early, more problematic one and if you'll use it constantly on the highway than except the turbo failure there is nothing endangering you. Just pay attention of the oil change periods and the condition of the timing chain driven oil pump and it'll be be good.