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.

If the noise is a metallic rattling noise, then you might be on the right track here. But as well as the timing chain, it could also be the tensioner that keeps that timing chain tight at fault. The fact that the noise goes away after a few seconds suggests that the tensioner, rather than the chain, is at fault. But they could both be worn.

What’s happening is that the tensioner is hydraulically operated and needs engine oil pressure to do its job. When the engine has been sitting overnight, there’s a slight time delay between it starting and enough oil pressure reaching the tensioner to tighten the timing chain and stop the noise. What you’re hearing is the chain flailing around until the tensioner steps up and takes the slack out of it, at which point it stops rattling and goes silent.

Why doesn’t it happen every time you start the engine? Because the tensioner needs time for the oil to drain completely out of it. If the engine has only been stopped a short time, there’s sill enough oil in the tensioner for it to build up pressure quickly and keep things quiet.

If you mean shuddering and vibration when you take off from rest, then you’re possibly experiencing the same problem that many owners of this model Nissan have already reported. The problem is caused by wear in the CVT transmission which is allowing the steel drive belt to slip. As the belt slips and grips and then slips again, the driver experiences less-than-smooth acceleration.

The safety recalls (which were actually technical service bulletins) you’re referring to all occurred within the North American market and haven’t been extended to Australian X-Trails (that I know of). Unfortunately, US consumer law is quite different from ours and consumers have very different rights and obligations.

It would be worth having the car assessed and then approaching Nissan Australia’s customer service department to see if there’s any help on offer. But given the age of the vehicle, I wouldn’t be holding my breath. That said, I totally understand your point of view, and 11 years is probably not a suitable lifespan for a modern automatic transmission, given we’ve been making cars for more than 130 years, and Nissan (in one form or another) for the last 90 of those.

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.

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.

Actually, it’s none of those things. This model Pulsar came with the option of a six-speed manual. But if it was an automatic Pulsar, it was fitted not with a conventional automatic, but with a CVT or Constantly Variable Transmission. Instead of a series of gears inside it, the CVT uses cones of different diameters linked by a flexible belt. By altering where on the cones the belt rides, the gearbox can produce different 'gears'.

The idea is that by providing an infinite number of ratios, the engine can always run closer to its most efficient speed, therefore improving fuel efficiency. It’s a great theory, but not all drivers like the sound and feel of a CVT which can feel pretty alien, especially at first. Some manufacturers, in an attempt to make the CVT feel more familiar, electronically engineer in fixed `ratios’ but, in reality, this removes some of the CVT’s efficiency-boosting potential.

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.

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.