Mazda Problems

Unless you’ve changed the way you drive, a sudden jump in fuel economy suggests something wrong with either the mechanical or electronic side of things. Have the vehicle scanned and see if it throws any fault codes. From there, you can work out what component is giving you grief and target the problem accurately, rather than mess around for weeks flying blind.

One reason for the sharp increase in fuel consumption could be that the vehicle’s diesel particulate filter (DPF) is full and needs to be regenerated. If you’re not doing long, highway miles, the computer can take matters into its own hands and dump extra fuel into the exhaust system in an attempt to get the exhaust hot enough to regenerate the filter. But you could also be dealing with a faulty fuel-pressure regulator, worn injectors or even something as simple as a blocked air filter.

Mazda Australia has previously told CarsGuide that it would love to get hold of a batch of the hot-shot Mazda 3 Turbos. And while the local arm of Mazda has asked head office for a batch of the all-wheel-drive hot-hatches, no decision has been confirmed as yet.

Mazda’s problem is justifying the cost of making the car in right-hand-drive form, and the complex mechanical packaging makes that even more difficult than usual. Designed for the North American market, the lack of a right-hand-drive variant will likely be the biggest hurdle to the car making it into showrooms here.

Mazda Australia is obviously keen on the idea as it would give it a competitive product to tackle the success of the VW Golf GTi, the Renault Megane RS and the soon-to-arrive new Subaru WRX. The bottom line? Cross your fingers, but don’t hold your breath.

Your car is certainly exhibiting the signs of a car with a blown head gasket. The smoke from the exhaust is one symptom, and so is the loss of performance. The oil leaks, could be part of the same problem, but could also be from somewhere else on the engine. Oil leaks have a cunning habit of being able to hide their true source.

On top of that, even the exhaust smoke and lack of performance could be down to something other than a head gasket problem, so the next step is to take the car to a workshop and have what’s known as a TK test carried. This test will chemically detect if combustion from the engine cylinders is finding its way into the coolant. If it is, you can be pretty sure that you have a blown head gasket.

At that point, you need to weigh up the cost of repairs to see whether you think it’s worth doing, given the overall condition of the car versus the cost of getting into something newer. If you really love the Mazda as much as you say, then maybe the cost of changing the head gasket will be acceptable compared with how you value the vehicle. And even if the repairs cost $2000 or even $3000 (which they could depending on how deep into the engine you need to go and what else you find wrong) there’s not much out there in today’s market for that money that represents anything even remotely decent.

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.

The Mazda 3 timing belt or chain question is a common one, but one with a fairly simple answer. Unless the Mazda 3 in question is the very first turbo-diesel model (sold in Australia between 2007 and 2009) then the engine powering it uses a timing chain rather than a rubber belt.

The exception was the 2.0-lire turbo-diesel which used a rubber, toothed timing belt. The design seems sound, however, and Mazda’s recommended replacement interval for the belt and its tensioner is every 120,000km. Make sure this has been carried out promptly, as a snapped belt will probably destroy the engine. A small sticker somewhere in the engine bay should record the most recent belt change. The complete kit to replace the timing belt on this engine is available for around $200 and you should budget another few hundred dollars to have the job carried out by a workshop. Best practice is to also change the water pump and thermostat at the same time as these live in the same area of the engine.

The task of the timing chain or timing belt is exactly the same: They take drive from the engine’s crankshaft to the camshaft and, in the process, keep all the moving parts in harmony. Many car makers moved away from a timing chain to the rubber, toothed drive belt as a way of simplifying engine design and driving down the cost of each engine. The rubber timing belt is also quieter in its operation and is also less prone to stretching (as a timing chain can) so the camshaft (commonly referred to as the cam) stays in perfect synch with the rest of the engine’s rotating parts. The rubber belt is a simpler design because it doesn’t need to be tensioned via oil pressure from the engine as many timing chain systems are.

The timing chain, meanwhile, is preferred by some manufacturers because it should last the lifetime of the engine and never need replacement. This isn’t always the case, however, and some engines designs from a variety of manufacturers suffer problems in this regard. But, in a properly maintained engine of sound design, the timing chain should never need attention, while the rubber timing belt generally has a replacement interval of between 60,000km and 120,000km, depending on make and model.

Mazda 3s have a pretty terrible record with power-steering faults. Some cars built between 2007 and 2008 were actually part of a nationwide Technical Service Program by Mazda to fix a problem that could leave you suddenly without power assistance for the steering. The program was not a recall as Mazda argued that even if the assistance failed, you’d still be able to steer the car, albeit with much greater input from the driver.

Mazda reckoned that cars outside those build dates weren’t affected, but yours is not the first later-model 3 I’ve heard of that has suffered similar problems. From what I can gather, the power steering assistance in your car uses a conventional hydraulic rack but instead of the assistance pump being driven by the engine (via a belt) it’s driven by an electric motor. So here’s my question: Do you notice any other symptoms when the assistance fails?

Any warning light on the dashboard or the radio cutting in or out are symptoms that other owners have mentioned at the same time as the steering has lost its assistance. Scanning the car electronically might throw up a few answers, but the instinct of many mechanics is that the problem is potentially as simple as a poor earth connection. A bad earth can occur in lots of places on a modern car and can create havoc with the car’s electrical systems (of which the power-steering on your car is one). Sometimes it can be as simple as a loose battery terminal, other times you might have to search for the bad earth. But that’s where I’d start looking.

This is one of the problems with the way the prices of band-new vehicles are haggled over. Had there been just a simple checkout price (as there is with nearly everything else we buy) this confusion probably wouldn’t have crept in. I take that, having asked for the tray upgrade, you then paid attention only to the final price being offered by the dealer.

Regardless of whether the dealer is trying to stall you with talk of a two month wait is a side issue. And perhaps you can hold out and force the dealer to supply the vehicle as per your contract of sale. Then again, if the mistake was a genuine one by a member of the sales staff (who could conceivably lose their job over such a blunder) then what’s the moral solution? Perhaps there’s a compromise to be made by both parties. I can understand you not wanting to pay an extra $7000 for a different type of tray, but surely that’s not the best result for anybody. In an ideal world, perhaps one solution would be for the dealer to provide the tray at their cost price (so they don’t lose money on the deal) and you get a cheap(er) tray because you’re not paying retail. Yes, it’s complicated. But that’s what happens when commerce meets karma.

There are a few things going on with insured values. The first is that insurance companies will – generally – do everything they can to pay out as little as possible against a claim. That means, they will usually take the lower number from a range of values, and that appears to be exactly what has happened here. If you take a look at the classifieds right now, you’ll see 2015 Mazda 3 Maxxes priced anywhere from $12,000 to the low-20s. Clearly, your insurance company has adopted the lower of those values as the one that represents market value for your car. Don’t forget, either, that the asking price in the advert is not always the actual price that will be paid.

There can be other influences, too. What condition was your car in before the crash that wrote it off? If it had existing damage or wear, that could have led your insurer to adjust downwards the pay-out price it was offering. And what about kilometres travelled? Generally speaking, every extra thousand kilometres over the average for that make and model reduces its value in the eyes of insurance companies.

As for a replacement vehicle, I’d be looking at some of the South Korean (Hyundai and Kia) offerings. These brands now have a jump on some of the opposition when it comes to technology and standard safety equipment. They also represent solid engineering and reliability, not to mention terrific factory warranties.

It sounds like there’s a bit of confusion here over what actually caused the glass to break. It’s not entirely unknown for sunroof glass to shatter in extremes of heat or vibration, and other times, a car that has been poorly repaired after a crash can put stresses on the glass it was never designed for. The glass could simply have been struck by a flying rock or piece of debris. How you interpret those things will determine whether you think the breakage is a valid warranty claim or not. The fact that the dealership that examined your car can’t say what those 'external factors' were, only deepens the mystery.

In the end, I approached Mazda Australia with your case, who agreed to take a second look at the circumstances. The good news is that Mazda has applied the benefit-of-the-doubt judgment and agreed to fix your car under warranty.

But it’s worth mentioning that any car owner unhappy with the service or consideration given by a dealership doesn’t have to let it rest there. All car brands have a customer service department, and this should be your next port of call. From there it’s on to the ACCC. In some cases it’s worth getting an independent inspection of any damage to try to come to a conclusion over what really happened. The State motoring clubs are a good starting point for this service.

This sounds like a classic case of checking and rechecking everything you did to find out where the job went wrong. I’ll assume the engine was running before the spark-plug change and, if so, then it’s likely that you’ve done something really simple that has brought the vehicle to a halt.

The first thing to check is that you have replaced the spark-plug leads in their correct order. This is a really simple mistake to make but it will definitely put an end to play if you get it wrong. Even experienced wise heads often tackle this job one spark plug and one lead at a time to avoid a tangle of leads and the ensuing mix up. While you’re there, check that the high-tension lead from the coil to the distributor cap hasn’t fallen out or become loose. Sometimes it will look as though it’s in place, but needs a push down on to its contact. Still at the coil end of things, check that none of the little spade terminals have been accidentally dislodged from the coil’s terminals.

Another common mistake is to simply buy new spark plugs and install them. In many cases, they need to be gapped correctly, that is, they need to have the gap between the two electrodes set at the correct distance for your engine. In the case of your car, the correct gap is 1.1mm (44 thou, for the old mechanics out there). Without the correct gap, the engine won’t run properly and, if the gap is out far enough, the engine may not run at all. Don’t assume the spark plugs will have the correct gap on the shelf at the spare part shop.

All this pre-supposes, of course, that the problem has occurred as part of the spark-plug change. The truth is that it could also be a coincidence where something with the fuel system has gone wrong at the same time as you decided to change the plugs. If that’s the case, it’s back to the drawing board in terms of a diagnosis, but the good news is that the engine in your car is quite a simple one and is a great engine on which to learn about mechanics. Above all else, don’t be discouraged and keep at it; home maintenance of a vehicle can be very rewarding and save lots of money.