Owners of the Nissan X-Trail diesel regularly report problems with glow plugs around 70,000 to 100,000 kilometres, often combined with battery issues. This combination can lead to starting difficulties, especially in winter. The solution requires timely replacement and a careful diagnosis of the entire electrical system. Want to know how to recognise these problems and what you can do about them?
Why glow plugs fail so quickly in the X-Trail diesel
Glow plugs in diesel engines preheat the air in the cylinders to make cold starts possible. They normally operate at temperatures between 850 and 1,100 degrees Celsius. In the Nissan X-Trail diesel, these components often turn out to fail earlier than expected. Most problems arise due to excessive voltage or heat.
When electrical current is supplied for too long due to a faulty relay or controller, glow plugs overheat. They can then swell, crack or even burst. This is a common problem with X-Trail models. In addition, enlarged probe tips can occur due to too much voltage. This requires immediate replacement.
Carbon build-up also plays a role. When carbon accumulates on the glow plug, combustion in the cylinder is no longer complete. This may point to a deeper engine problem. For example, there may be too much fuel in the combustion chamber.
Recognise starting problems by these symptoms
The first signs of glow plug problems are often subtle. The engine warning light comes on, indicating that the engine electronics have detected a fault. Starting difficulties in winter are a clear sign that the glow plugs are not heating up quickly enough.
Other symptoms are:
- Engine misfiring while starting or accelerating
- The car starts better later in the day when the engine is already warm
- Longer starting time at low temperatures
- Irregular engine speed when starting
A classic symptom with X-Trail diesels: the engine is difficult to start in the morning. Later in the day the engine gives no trouble. The engine is then already warm and no longer relies on glow plugs for ignition.
The role of the glow plug relay and timer module
Often the problem is not with the glow plug itself, but with the glow plug timer module or the relay. The timer component controls how long the glow plugs receive voltage. When it fails, the glow plugs receive either not enough voltage or none at all.
You can diagnose this yourself by placing a multimeter on a glow plug terminal. Have someone try to start the car while you monitor the voltage and duration. Compare this with the factory specification in the workshop manual. Note: the glow plug relay can be damaged by jump leads. Always use a 12‑volt power source for jump starting.
Battery problems worsen glow plug symptoms
Although battery failure is technically a different issue, battery problems can cause or worsen glow plug symptoms. A weak battery supplies insufficient voltage to the glow plugs, leading to starting difficulties. This explains why many X-Trail owners experience both problems at the same time.
Always check the battery connections and condition first before replacing glow plugs. A poor connection or corrosion on the battery terminals can cause the same symptoms as faulty glow plugs. Test the battery voltage with a multimeter. A healthy battery shows at least 12.6 volts with the engine off and 13.5 to 14.5 volts while driving.
Underlying causes you should check
Before replacing glow plugs, it is wise to check the entire electrical ignition system. Otherwise, you will be replacing glow plugs that will soon fail again due to the same underlying cause.
Possible causes are:
- Injection timing that is too early, which unnecessarily increases combustion temperature
- Leaking injectors that cause higher combustion temperatures
- Diesel entering the engine due to a faulty fuel pump or injectors
- Oil entering the combustion chamber due to wear
Quickly finding these causes helps to minimise further engine damage. A swollen probe tip at the bottom of the glow plug usually indicates oil in the combustion chamber. This is often a sign of normal wear, but in severe cases may require more expensive repairs.
Practical replacement tips for X-Trail owners
Replacing glow plugs in a Nissan X-Trail diesel requires care. Glow plugs have a tightening torque of around 50 newton metres, but a breaking point of only 35 newton metres. Over‑tightening therefore quickly leads to breakage.
Some X-Trail models require removal of other components such as intercoolers to gain access to the glow plugs. Always use the correct tools and make sure you do not cross‑thread. This can cause serious damage to the cylinder head, resulting in an expensive repair.
When removing old glow plugs, patience is important. Glow plugs can seize due to carbon deposits and corrosion. Never force them, but use a penetrating oil if necessary and allow it to soak in for several hours before trying again.
When you should go to a workshop
If you have experience working on cars, you can carry out diagnostics with a multimeter. However, many X-Trail owners note that the glow plugs are difficult to reach. In some cases, it is wiser to call in a workshop.
Consult a specialist if you are unsure about the voltage going to the glow plugs or when several components fail at the same time. A diagnostic device (this device reads fault codes from the vehicle electronics) helps to pinpoint faults accurately and distinguish between glow plug problems, relay defects or sensor failures.
With regular maintenance and early diagnosis, you can prevent expensive engine damage to your Nissan X-Trail diesel. Replace glow plugs in good time at around 80,000 kilometres, check the battery annually and have the entire electrical system checked immediately if you experience starting problems.
‘ On the Carnews website you will find extensive information about common problems, maintenance tips and practical solutions for various car models. ’
Find out more about your Nissan X-Trail
The Nissan X-Trail diesel has more known points of attention that you as an owner should bear in mind. On the Carnews website you will find extensive information about common problems, maintenance tips and practical solutions for various car models. Discover what other owners experience and how to maintain your car in the best possible way.
Frequently asked questions
The text appears to be an explanation of glow plug and battery problems in a Nissan X-Trail diesel, not a concrete question. Without a specific question on this topic, I cannot formulate a targeted answer.
The text describes causes and symptoms of faulty glow plugs and related electrical problems in a Nissan X-Trail diesel. Common causes are overheating due to incorrectly controlled voltage, carbon build-up, oil leakage into the cylinder and mechanical damage during (dis)assembly. Symptoms include hard starting (especially when cold), engine misfiring and an engine warning light, with the relay or glow plug timer sometimes being the culprit instead of the plugs themselves. A weak or faulty battery can also cause similar starting problems and should be checked first.
The glow plugs in a Nissan X-Trail diesel preheat the air in the cylinders so that the engine can start properly, especially in cold weather. Common causes of failure are overheating due to a faulty relay or timer module, carbon build-up, oil in the combustion chamber and mechanical damage during (dis)assembly. Symptoms include difficult starting in cold conditions, misfiring, an illuminated engine warning light and better starting when the engine is already warm. Checking the battery, glow plugs, relay/timer and possibly the injectors is necessary to find the correct cause.
The text describes common causes and symptoms of glow plug problems in a Nissan X‑Trail diesel, including overheating due to a faulty relay or timer module, carbon build-up and mechanical damage during (dis)assembly. It also explains that starting problems in cold weather, an illuminated engine warning light and misfiring are typical symptoms. In addition, it emphasises that the glow plugs themselves are not always to blame; often the glow plug relay or timer module is the culprit, and a weak battery can cause similar complaints. Finally, the text gives practical replacement tips (such as tightening torque and taking care during assembly) and the advice to consult a workshop if in doubt.