Articles by Marcus Craft

The BYD Shark 6, the first plug-in hybrid electric ute to hit Australia's shores, is leading the charge of plug-in hybrid electric utes, followed closely by PHEV versions of the Ford Ranger and GWM Cannon Alpha.It's an innovative approach and has generated plenty of excitement, but is the Shark 6 - with no 4WD, no low-range gearing and no diff-locks - a novelty or a sign of things to come?

Q: Do diesel engines have spark plugs?A: No, diesel engines do not have spark plugs.What are spark plugs? What do spark plugs do?Spark plugs are located at the top of the cylinder head in petrol-fuelled internal-combustion engines. As the name implies, these engines rely on the combustion process to power the engine. And a spark plug – as the name implies – is an electrical component which produces a spark that ignites the petrol-air mixture, causing the combustion process to kick off in order to power the engine. That spark is created between two electrodes at the tip of the plug as a result of a high-voltage charge received via the ignition coil at the other end of the spark plug.What kinds of cars have spark plugs?Spark plugs are found in cars with petrol engines.Do diesels have spark plugs?No, they don’t.How many spark plugs are in a diesel?None, but they do have glow plugs which we’ll get to in a couple of sentences below this. Most diesel engines run on one glow plug per engine cylinder.Why don't diesel engines have spark plugs?Because diesel engines use high compression, rather than an actual spark, to ignite the fuel. Air is drawn into the engine cylinder and compressed to an extremely high pressure and consequent temperature.What do diesels have instead of spark plugs?Glow plugs.What do glow plugs do in a diesel engine?As mentioned above, diesel engines use high compression, rather than an actual spark, to ignite the fuel. So, instead of spark plugs, diesel engines use glow plugs, electrical heating devices located in each cylinder of the diesel engine, which preheat the air in the engine’s cylinders to expedite the combustion process necessary to start the engine.A glow plug in a diesel-fuelled vehicle is only needed during the ignition process, whereas a spark plug in a petrol-fuelled vehicle works continuously while you’re driving.Do all diesels have glow plugs?No, not all diesel engines have glow plugs.When the diesel-air mixture is compressed quickly in a diesel engine, it ignites without any need for an actual spark and that produces heat enough to kick-start the combustion process.But smaller diesel engines have difficulty maintaining the temperature necessary for combustion and the purpose of glow plugs is to warm the diesel-air mixture in order for it to combust of its own accord.Many larger diesel engines don’t need any glow plugs because their diesel-air mixture ignites without any need for assistance. . The diesel-air mix has sufficient heat coming from the air, which becomes increasingly hotter as it is quickly compressed.How does a diesel engine work?This is best explained by a panel of diesel experts over at Cummins who came up with this nifty explanation … and it reads like poetry to me:“In general, a diesel engine works by using a piston to compress air to increase the temperature in the cylinder and then injecting atomised diesel fuel into this cylinder.“When the fuel comes into contact with the high temperature, it ignites, creating energy that drives the piston down transferring energy to the crankshaft and through the powertrain.“This process is repeated over and over again at a high speed, making a diesel engine a powerful piece of technology. “Different types of diesel engines will have varying compression ratios. The compression ratio of the diesel engine impacts how much power the engine puts out. The higher the ratio, the more power is generated.”Couldn’t have said it better myself.

Q: Can you mix 91, 95 or 98 petrol together? A: Yes, you can, as long as you always use fuel with a higher RON (Research Octane Number, also known as octane rating or octane level, is an indicator of fuel stability, and recognised industry- and world-wide. The numbers in the RON denote the level of pressure generated within a vehicle's engine during fuel combustion) than your vehicle’s manufacturer-specified minimum octane requirement.

Jeep does two things well: it makes some great off-roaders (e.g. the Jeep Wrangler Rubicon) … and it hides a stack of Easter eggs (subtle design features, not chocolate) in its vehicles.

Most of the 2025 Toyota LandCruiser 300 Series line-up has undergone a recent comprehensive update - along with price increases to match - but while the third-from-top Sahara gets a $1119 price rise, it has received no updates this time around.Can the 300 Series stay viable in an increasingly competitive 4WD market? More importantly, is this Toyota 4WD wagon still an off-road champ?

Is BYD's Shark 6 all it's cracked up to be?

Can you use your phone while driving if it’s mounted?

Black ice is “a dangerous type of ice that forms on roads and that is so thin that it cannot be seen by a driver”, according to the Cambridge Dictionary.

The Premcar-boosted Nissan Patrol Warrior was an impressive 4WD wagon from its first appearance a few years back.Well, now the entire 2025 Patrol range - including the Ti-based Warrior - has undergone an update.Sure, the changes don't yield any performance gains and they are cabin-based but they do include a new bigger touchscreen multimedia system, wireless charging and an off-road monitor.

It's big, brash and in your face but is the gargantuan GMC Yukon Denali worth your consideration? General Motors Specialty Vehicles is banking on it. Packing a 6.2-litre V8 petrol engine, eight seats and a big features list, this top-shelf US 4WD has a price tag just under $175,000, making it a lot more expensive than most wannabe rivals in Australia. The Denali is here whether you like it or not.