Great Wall Problems

In order to find the remedy, you first need to know the cause. On this vehicle, the P0300 code indicates a misfire in one or more of the cylinders of the engine. In the majority of cases, this can be traced to a faulty coil, high-tension lead, spark plug, computer or even the fuel system. The warning shows that one of the cylinders is not firing as cleanly as it should be, so those are the basic thigs to start with. The problem could be as simple as moisture inside one of the coils or its fittings, or even a simple dodgy spark plug. If that’s the case, replace all of them, rather than just the one that’s faulty, as the rest are also likely to be getting towards the end of their life.

There are plenty of reasons why a diesel won’t start in the morning. This can often be traced back to a problem with the fuel system or the glow-plugs which are needed to warm the combustion chambers before the diesel will ignite.

As for the noise, it pays to remember that diesel engines are inherently noisy, but if you’ve owned the car for a while and are familiar with its normal level of racket, then any new or louder noises signal a problem. If, indeed, the new noises are connected to the engine’s refusal to start easily, you might be looking at an engine with worn out internals. At that point, it’s time to recondition or replace the original engine.

But before you do any of that, have a diesel specialist look at and listen to your engine running, and you might find the problem is a simple one after all.

That’s an odd one, to be sure. I’ve never heard of an engine that used different sized spark plugs in different cylinders, so you’d have to assume it’s the result of somebody only doing half a job when the car was serviced.

There’s at least one possible explanation for this, though. You might find that one of the spark plugs is difficult to reach or access. In that case, a lot of amateur mechanics will leave that one plug and replace the others with new plugs that have a different sized insulator (the white, ceramic bit you can see poking out of the cylinder head). It’s always best practice to replace spark plugs as a complete set, but lazy mechanics will cut sometimes corners.

There’s also a very slim chance that a previous mechanic has used a different sized spark plug during a routine replacement because they didn’t have four new ones that matched.

Spark plug size is critical in many respects. As well as having the correct threaded section to fit the cylinder head, a spark plug’s internal dimensions are crucial to ensure it doesn’t poke too far into the combustion chamber and make contact with the piston. It also needs to be located correctly in the combustion chamber to ensure proper ignition of the fuel.

You’d be surprised at how much load an air-conditioner places on an engine, especially when it’s idling and not making much power or torque. It can certainly be enough to make the engine labour and drop revs, forcing it down to a speed where it can no longer idle smoothly; almost as if it’s trying to stall.

Carmakers get around this by programming an idle-up function into the car’s computer. This detects that the air-con has been switched on and will then tell the engine to idle a little faster to keep everything running smoothly. If this idle-up function is not working, you can get the precise symptoms you’ve described. However, if this is the cause then make it GWM’s problem to put right, as it amounts to a fault and should be covered by the new-car warranty.

The failure to load the sensors is probably a centralised computer problem, since it’s more than one sensor (it would be an amazing coincidence if three sensors died at once). Either the Bluetooth connection is iffy, or there’s a software problem with reading what the sensors are saying.

I’m unsure how Great Wall can call the tyre-pressure sensor monitoring system a consumable. Yes, things like brake pads, tyres and batteries are considered consumables and not covered by a new-car warranty, but the tyre pressure monitoring system should last the life of the vehicle and is an important safety feature. I’d be ignoring the dealer and talking directly to GWM’s Australian customer service department and asking the tough questions. Australian consumer law is pretty clear on matter such as this one.

One of the biggest criticisms of the 2017 Great Wall Steed was that it had Isofix restraint anchor points in the seat bases, but no legal top-tether anchoring points at the top of the seat. As such, the vehicle was unsuitable for carrying children of child-restraint age with safety body ANCAP stating the vehicle was “not suitable for transporting young children”. This was a major reason the vehicle scored just two out of five safety stars from ANCAP.

It’s possible to retrofit top-tether points, but, because of the consequences of getting this wrong, the changes would have to be approved by a consulting engineer and signed off by the Tasmanian state registration authorities.

In modern vehicles, there are usually two oil warning lights. The first – an orange or yellow light - is to alert you that the oil level in the sump is becoming too low. This is easily fixed by stopping and topping up the engine oil. Provided you do it promptly and don’t ignore it, you shouldn’t do any permanent damage.

The second light is a red one and indicates that your engine has insufficient oil pressure to lubricate the moving parts. Sometimes, when this light shows, it’s already too late and permanent damage will have been done. But if you do see the oil-pressure warning light, drive to the nearest safe place to stop and switch off the engine as soon as possible. The vehicle will then need to be towed to a workshop to be checked out.

If you stopped the engine early enough, you might be able to repair the cause of the low oil pressure. But in many cases, it’s all over and done by the time the light flickers on, and you may need a replacement or reconditioned engine.

Engine longevity is closely linked to how well maintained it’s been. As such, there’s no definitive lifespan for a specific make and model. An engine that has been treated well and maintained correctly will easily outlast the same make and model engine that has been driven hard and missed critical servicing and upkeep.

That said, 260,000km seems like a lot of kilometres for this vehicle. Which is not to suggest it’s necessarily ready to explode, rather that you’d have to know for sure it was a pampered car with an impeccable service record for it to be a reasonable bet. But a gamble of some sort it would definitely be.

The last decade of dual-cab four-wheel-drive utes have emerged as the tow-vehicles of choice, and you see them everywhere filling roles exactly like the one you have planned. Popular models include the Ford Ranger you’ve nominated, Toyota HiLux, Mazda BT-50, VW Amarok, Mitsubishi Triton, Nissan Navara and Isuzu D-Max. But there are also cheaper alternatives including makes like the South-Korean made Ssangyong and various Chinese brands like LDV and Great Wall.

Just make sure you know exactly how much you need to tow before making a decision as some of the cheaper models don’t have the same outright towing capacity and even if they do, some of them don’t have the engine performance to make towing as easy as it should be. For parts availability, the Toyota would be king in really remote areas, but any of the major brands are pretty well covered in Australia.

Meantime, don’t rule out ute-based wagons such as the Ford Everest, Isuzu MU-X, Mitsubishi Pajero Sport and Toyota Fortuna. These offer better ride comfort when unladen thanks to more sophisticated rear suspensions and most have as much or almost as much towing capacity as their ute brethren.

It all depends on the model and variant of the vehicle you’re talking about, but, generally speaking, the fuel rail pressure sensor on a turbo-diesel engine will be somewhere along the fuel rail. But, even if you know for absolutely certain that this sensor is the problem, we have to advise against any amateur mechanic taking on this, or any other, job that deals with the fuel system. That’s because the fuel systems on a common-rail turbo-diesel run at incredibly high pressures. So they’re dangerous things to fiddle with.

In some cases, the pressure could be enough to slice fingers off. Which means you have to know the exact process to follow in order to bleed off any residual pressure in the fuel system (even if the engine hasn’t run for days) before you can safely tackle jobs like this one. Leave it to the experts, in other words. Also, a specialist is a chance to be able to make a more accurate diagnosis than the one given by an online forum of dubious credibility.