Nissan Problems

While the ZD30 engine should have been a major step forward in terms of technology with common-rail technology and double overhead camshafts, in reality, the engine was not one of Nissan’s finest moments. Bottom end failures were not uncommon with cracked pistons necessitating full rebuilds.

Several causes have been suggested including poor fuel-air ratio management and boost spikes form the turbocharger putting sudden, huge loads on the engine’s internals. Either way, though, the engine is far from remembered fondly.

CarsGuide has looked at this engine in depth, and even published a guide to the Nissan Patrol ZD30 engine.

This is a typical car company response to the problem of pedal error which has raised its head many times since about the 1980s when car maker started getting sued by drivers who had pressed the wrong pedal, but claimed the car had accelerated of its own accord.

The solution was to make sure that if the driver accidentally pressed the throttle, if they also pressed the brake in panic, the car would stop accelerating. By pressing the brake and throttle together in your car, you’re reproducing that exact situation. So, really, there’s nothing wrong with your car, and it’s only doing what it’s programmed to do.

A lot of drivers don’t like this feature, however, as it means the slightest hint that both the brake and throttle are applied at once is enough for the car to cut its power and not move, as you’ve discovered. Many have found that when trying to enter fast moving traffic or make a quick lane change, and operating both brake and throttle at the same time for a quick getaway, this function is actually dangerous.

Unfortunately, there’s not a lot you can do about it other than learn to not even brush the brake pedal when you want to make a quick start.

This sounds awfully like badly worn transmission. The Dualis in automatic form used what’s called a CVT. Instead of gears inside the transmission, the CVT has pulleys and metal belts that vary their relationship and, therefore, create the various 'gear ratios' the car needs.

When these pulleys and belts wear, they can start to make the noise you’re reporting. And, just like your car, it will get noisier as time passes. Unfortunately, you’re probably looking at a transmission overhaul or rebuild. If you continue to drive it as it is, you’ll almost certainly do more damage, although it sounds like the real damage is already done.

Take the car to a transmission specialist who will be able to accurately diagnose the noise and take it from there.

This mightn’t be too hard to figure out as the GU Patrol used a purely mechanical engagement system for the transfer case and four-wheel-drive system. Unlike newer designs with rotary knobs and electronic control, there’s really not to much to go wrong with the Patrol’s setup assuming it’s a selector problem. Make sure the selector rods are all connected properly and that they’re not binding or loose under the car.

However, if the lever is engaging and the front drive-shaft is not turning the front wheels, then you may have a hub problem. Free-wheeling hubs are great for saving fuel, but when they go wrong, it can often mean the drive doesn’t reach the front wheels. At that point, you have a bigger job on your hands. The same symptoms could also be a result of a broken front differential which is not sending the drive out to the front wheels. Finally, the transfer-case itself may be at fault. If it’s not sending the drive forward, there’s no way the vehicle will achieve four-wheel-drive.

Also, to maximise your chances of engaging four-wheel-drive, make sure the vehicle is stationary at the time and the transmission is in neutral. In fact, this is essential for moving between two and four-wheel-drive in many types of off-roader.

Short answer: No. The park-brake warning light is there to help prevent you driving off with the park brake engaged. But really, all the lights on the dashboard should go off when you turn off the ignition and lock the car. The possible exception is a flashing light to warn would-be car thieves that the car is alarmed.

Dashboard lights (and other lights) that randomly light up when the car is switched off can be a sign of a slowly dying body computer, but you should never ignore a warning light for the braking system. You could find the light is being triggered by an actual fault in the park brake mechanism, including maladjusted cables, worn brake pads or some other mechanical problem. But we’d also check the owner’s manual to make sure that the same warning light is not designed to be triggered by some other braking problem like, for instance, low brake fluid level.

You need to be strategic with problems like this one, and not just throw new parts at the car which may or may not fix it.

That means the first thing to do is electronically scan the car to see if the on-board computer knows what’s wrong. Hopefully this information will lead you to either the ignition or fuel system and, from there, you can home in on the fault.

Ignition-wise, you may have a computer, wiring, spark plug issue or about a thousand other things on a modern, electronically-controlled car like this one. If the fuel system's at fault, you need to check things like the filter and fuel pump delivery pressure and volume and even the age of the fuel. Modern fuel doesn’t like to sit around for any length of time, and many’s the car that has been sidelined through petrol that has lost its mojo.

While the G35 Skyline is not a common car on Australian roads, its driveline is pretty well understood. Even so, finding a workshop that specialises in this make and model would be a good idea.

If the problem occurred immediately after you replaced the carpet and seats, I’d say there’s a very good chance you’ve unclipped a wiring plug or connector to remove the interior, and failed to reconnect it afterwards. A lot of modern cars have airbags in the actual seat (the side airbag usually) and the wiring often runs under the seat.

The best move would be to remove the seats again and check for loose wiring or wiring or connectors that have been damaged of misplaced in the process of the interior’s removal. But before you touch anything under there, disconnect the car’s battery. That ensures you won’t have an accidental airbag deployment that could injure you while you’re working in that space.

A loss of engine power can be due to many things. Most mechanics will start with a check of the fuel and ignition systems to check for things like dud spark plugs, ignition timing, broken ignition leads and coils and whether or not enough fuel is reaching the engine (worn fuel pump or blocked fuel filter). If all that checks out, then the search will move to mechanical things like the camshaft timing, and whether there’s a leaking engine valve or a vacuum leak somewhere.

The 2.5-litre petrol engine in your X-Trail is a very well known quantity, so there’s plenty of expertise out there. A workshop that deals with Nissans in particular may have seen exactly this problem before and will be able to go straight to the cause.

Meantime, don’t rule out the really obvious stuff like a dragging brake that could be making the vehicle feel sluggish.

Many workshops would start with a simple tune-up and service to tackle this problem. Cars lose performance over the years and it’s often as simple as a good tune-up including a change of spark plugs, filters (air and fuel), spark plug leads and a check of the ignition coils (in petrol models).

If you have the diesel-engined version of the X-Trail, it would also be worth checking to see if the intake manifold has become partially blocked with black gunk that is a by-product of the car’s emissions-control system.

A good service and tune might bring performance back to how you remember it, but don’t ignore the simply things like a faulty accelerator pedal calibration, or slack transmission that is making the car feel lazy. Even low tyre pressures can make a car feel lethargic in terms of both steering and how it accelerates.