Mazda 6 Problems

Most mechanics will do a complete check up and tune of the engine as part of tracking this problem and it’s a good start, because a new set of spark plugs and plug leads might just fix this problem. But that won’t always be the case. As such, you could be looking at a dud sensor somewhere in the engine bay that is telling the on-board computer to shut things down or, at least, not providing the computer with enough information to keep it all running. For this reason, an electronic scan of the vehicle should also be carried out at the same time to see what fault codes are cropping up.

A prime suspect for this behaviour would be what’s called the engine’s stepper motor which is a small electric motor that controls the throttle body and, therefore, the car’s idle speed. If this motor is maladjusted or faulty, it could cause the engine to either idle roughly, too slowly, or stall altogether. But have the scan done before rushing out to spend money on parts that may or may not be the problem.

It certainly looks like that could be the case. Mazda HQ has announced plans to stop production of the 6 at the plant that supplies Australian 6s, so barring a switch to a new supply-factory, that would seem to be so. There's a sense that some Mazda factories will continue to build the 6, but the suggestion is that this will only be for some limited Asian markets.

Unfortunately for those who like conventional vehicle packaging, the almighty SUV has just about killed off the traditional sedan and station-wagon.

The starter motor on this vehicle is located down low on the front of the engine. Conventional wisdom is to remove the air-box and part of the intake trunking to access the starter motor's fasteners and wiring, and then remove the starter itself from below the engine bay after removing the plastic underbody protection panel. Don't forget to remove the negative battery terminal before starting any of this.

Mazda’s 6 has always had a pretty good reputation in the trade for its reliability and durability, but globally, there have been a few concerns with the automatic transmission. The first of those is a situation where the transmission goes into limp-home mode. At that point, it can suffer slurred shifts and a lack of acceleration. It doesn’t seem a common complaint in Australia, but it’s reckoned to be caused by the transmission fluid becoming contaminated with small iron particles (possibly swarf from the production process) becoming attracted to the magnetic sensors inside the transmission. At that point, the sensors lose the plot and the information going to the computer becomes garbled.

The other thing seen (mostly in the US) has been a whining noise from the transmission. Inspections have shown this to be caused by a damaged bearing in the transmission, possibly the victim of misalignment of the gearbox casing. Again, it’s not a common fault showing up here.

Overall, the Mazda 6 seems one of the better bets out there in reliability terms.

Mazda is unlikely to increase the number of its passenger car models, given the contracting nature of such body styles in favour of crossovers and SUVs.

Also, note that a CX-4 has existed in China for a number of years, slotting tightly between the CX-3 and CX-5 as a sleeker coupe version of the latter, so if you do see a '4' (or, more likely, a '40') on the tailgate of a Mazda in the future, it might be sat on an SUV-shaped rather than hatchback-shaped five-door.

Probably not, sadly.

The slower-than-anticipated sales of the Mazda6 series over the past decade, combined with Mazda's hesitation to replace the existing, nine-year-old model, suggests that there is not a larger sedan in the pipeline.

However, with Mazda marching upmarket and its ties with Toyota strengthening, a joint-venture project with Toyota or even Lexus, using Mazda's new rear-drive platform and inline six-cylinder engine range, may make a model-sharing premium flagship – like a Mazda7 or even Mazda9 – a possibility.

But please don't hold your breath on this one because it is merely conjecture on our behalf.

Mazda is unlikely to introduce a sedan larger than the Mazda6, due to the declining sales of larger sedans globally in favour of SUVs.

However, with Mazda marching upmarket and its ties with Toyota strengthening, a joint-venture project with Toyota or even Lexus, using Mazda's new rear-drive platform and inline six-cylinder engine range, may make a model-sharing luxury flagship – a modern-day 929 in other words – a possibility.

But there are currently no plans that we know of pertaining to such a model, sadly.

We hope this helps.

This is a known problem in the Mazda turbo-diesel, and many owners have suffered similar failures. The problem begins with the formation of hard, carbon deposits in the top end of the engine which eventually find their way into the engine’s sump and block the oil pick-up. When that happens, the engine can’t pump oil efficiently and some parts of the engine become oil-starved. That’s when a build-up of friction and, therefore, heat, will cause a catastrophic failure with the attendant metal shavings that were subsequently discovered in your engine.

So why was the problem missed? An enthusiastic mechanic will always have a look at the oil that comes out of an engine, looking for just the symptoms you’ve noted. A really keen technician will sometimes even cut the old oil filter open to check for anything that shouldn’t be there. Unfortunately, in the context of a busy workshop with price-conscious customers, this doesn’t always happen. In the Mazda’s engine, the normal practice should be to check the strainer that covers the oil pick-up, but, again, that may not have been the case with your engine. If the workshop you used was a Mazda dealership, I’d be asking management why that process wasn’t followed. Even then, it’s difficult to say whether this check would have saved your engine, as the damage may already have been done.

Let’s start with the basics here, Bryan, before lashing out on mechanics. Are the tyre pressures where they should be? A tyre can be pretty under-inflated before that’s actually obvious to the eye, but a tyre with an incorrect pressure can be harder to turn. Next, what about the wheel alignment settings? Has the car bounced off a kerb lately? Has there been any incident that could have wrenched the front end out of alignment? When was the last time the wheel alignment was checked?

For all of that, however, I’m tempted to suspect that there’s something wrong with the valving in the power-steering rack. I’d be having the rack checked for any foreign matter inside that could be blocking the valves or in some other way preventing the rack from guiding the wheels smoothly in both directions. A dodgy steering system is an obvious safety issue, so don’t mess about having it checked.

It all depends on whether you bought the car privately or from a licensed used-car dealer. If it’s the latter, you might have some redress under the mandatory warranty conditions in your State. If you bought the car privately, I’m afraid there’s no comeback at all beyond contacting the seller, explaining the situation and perhaps coming to an arrangement on a refund or part-refund. I wouldn’t be holding my breath, however, and a private seller usually has no obligations whatsoever to make your problem their problem. Did you have the car independently inspected before the purchase? If you did, I’d be taking the matter up with whoever did the inspection, because a faulty transfer case should perhaps have been picked up as part of any pre-purchase test.

If the transfer case is damaged beyond repair, you’ll need a new one. The problem there is that the only Mazda 6 that featured this driveline (with a transfer case) was the MPS model which only sold in small numbers. So you might have trouble finding a second-hand one. Even the main gearbox (a six-speed) was different to the manual gearbox (a five-speed) on the other Mazda 6 models.