The ignition system is one of the most critical components in a gasoline engine. Nissan Murano Z52. When a car begins to operate unstably, loses dynamics, or fuel consumption increases, most often the reason lies precisely in the wear of the spark plugs. For owners of a crossover with a VQ35DE engine, this issue is especially acute, since access to the rear cylinders requires certain manipulations.
Many car owners put off visiting a service center, believing that the problem will solve itself or that replacement is too complicated a procedure. However, ignoring maintenance dates can lead to failure of the ignition coils, which will increase the cost of repairs significantly. In this article we will look in detail at how to choose the right spare parts, what tools you will need and how to do the work yourself without resorting to the services of dealers.
Replacement timing and signs of wear on VQ35DE
The manufacturer recommends scheduled replacement of ignition elements every 45,000 - 60,000 kilometers. In practice, taking into account the quality of domestic fuel and traffic jams, the resource can be reduced to 40,000 km. If you notice that the car jerks when accelerating or that starting the engine in cold weather has become difficult, this is the first signal to action.
Engine VQ35DE It is highly sensitive to spark quality. Worn electrodes lead to misfire, which causes the catalytic converter to overheat. Catalytic converter - the part is expensive, and replacing it will cost much more than a set of new spark plugs. Therefore, regular diagnostics of the condition of tips and insulators is the key to a long motor life.
- 🚗 Increased fuel consumption for no apparent reason
- 📉 Loss of engine power during acceleration
- 🔥 Jerks and dips when pressing the gas pedal
- 🔧 Difficulty starting the engine, especially in cold weather
Don't wait for the lamp to light up Check Engine. On Nissan Murano Z52 The self-diagnosis system may respond to misfires with a delay. It is better to carry out a visual inspection during the next maintenance in order to identify cracks on the ceramics or carbon deposits on the electrodes at an early stage.
⚠️ Attention: If there is a thick black soot visible on the spark plugs, this indicates problems with the crankcase ventilation system or valve stem seals. Simply replacing the spark plugs in this case will not solve the problem; engine diagnostics will be required.
Choosing the right spark plugs for Murano Z52
The choice of components for a Japanese car must be approached with maximum responsibility. For the 3.5 liter engine (VQ35DE), iridium spark plugs are standard. The use of conventional nickel analogues is not recommended, since they cannot withstand the high temperatures and loads of this particular motor, quickly losing their properties.
Original article for Nissan Murano Z52 — 22401-6XU0A. These are iridium spark plugs with a gap of 1.0 mm. Certified analogues from the Denso and NGK brands, which are often supplied to the assembly line, have also proven themselves to be excellent. The main thing is to avoid fakes, of which there are a huge number on the spare parts market.
- 🛡️ Original candles Nissan with iridium tip
- 🏭 Replacements for Denso VKA20 or NGK SILZKR7B11
- ⚙️ Proven analogues from Bosch or Champion brands (only with iridium)
Pay attention to the packaging. The original has clear printing, high-quality printing and protective holograms. The color of the body should be white, without yellowness. If you see that the thread is poorly cut or the insulator has microcracks, you should absolutely not use such a part.
- Up to 50,000 km
- 50,000 - 100,000 km
- More than 100,000 km
- I bought it used and don't know
Preparing tools and work area
Before starting work, you must prepare the appropriate set of tools. You will need a standard socket set, a torque wrench and, most importantly, a spark plug wrench with a rubber insert. A regular head may not hold the spark plug when removed from a deep well, which will cause it to fall inside the cylinder.
To access the rear cylinders on Nissan Murano Z52 you will have to dismantle the plastic decorative engine cover and, possibly, unscrew some of the fastenings of the intake manifold or throttle assembly, depending on the modification. Be sure to disconnect the negative terminal of the battery before starting any electrical work.
- 🔧 Spark plug wrench with extension (well depth about 10 cm)
- 🔨 Ratchet driver and set of sockets for 10, 12, 21
- 🧼 Compressed air cylinder for blowing out wells
- 📏 Torque wrench for precise tightening
It is ideal if you have access to a compressor or a bottle of compressed air. This will clear the area around the spark plugs from dust and small debris before unscrewing them. Dirt entering the cylinder when removing the spark plug can lead to scoring on the walls of the liner.
Step-by-step replacement instructions
The replacement process begins with removing the plastic cover on the engine. Unscrew the fastening bolts, carefully pull the cover up and remove it. Next you need to remove the ignition coils. They are fastened with 10 mm bolts. Disconnect the electrical connector by pressing the latch and unscrew the fasteners.
After removing the coil you will see a spark plug. It's important to take your time here. Blow out the spark plug well with compressed air, removing all dust and dirt that has accumulated on top. This is a critical stage that many people ignore and then are surprised when sand gets into the combustion chamber.
☑️ Preparing to replace spark plugs
Carefully unscrew the spark plug with a spark plug wrench. If the spark plug is stuck, do not try to tear it off abruptly; it is better to slightly warm up the joint (if the engine is warm) or use a penetrating lubricant, applying it to the threads from the outside, avoiding getting inside. Pull the candle out smoothly, making sure that it does not fall into the well.
Before installing a new spark plug, be sure to check the gap between the electrodes. Although the gap on iridium spark plugs is often not adjustable, it won't hurt to check. Install the spark plug into the well, tighten it by hand as far as it will go so as not to strip the thread, and then tighten it with a torque wrench.
Tightening torque for spark plugs VQ35DE is approximately 23-25 Nm. Excessive tightening can lead to deformation of the O-ring or breakage of the ceramic insulator, and weak tightening can lead to burnout and overheating. After installing all the spark plugs, replace the coils and decorative cover.
⚠️ Attention: If, when unscrewing, the old spark plug breaks and part of the thread remains in the block head, do not try to unscrew it with a pin driver without preheating or special means. It’s better to call a specialist to avoid damaging the threads in the aluminum.
What to do if the ignition coil cannot be removed?
If the coil is stuck to the spark plug, do not use brute force. You can gently rock it from side to side, while simultaneously pulling it up. Sometimes using WD-40 applied to the joint helps, but you need to wait 10-15 minutes so that the liquid does not get on the contacts.
Typical maintenance errors
One of the most common mistakes is incorrect tightening torque. Many car owners tighten the spark plugs “all the way” or, conversely, do not tighten them, believing that the rubber gasket will still seal the connection. As a result, heat dissipation is disrupted, and the spark plug begins to overheat or, conversely, gases leak.
Another mistake is mixing old and new candles. Never put new spark plugs in one cylinder and old ones in another if you are changing them one at a time. This will lead to uneven engine operation. Change the entire set to ensure equal sparking conditions in all cylinders.
| Parameter | Value for VQ35DE | Note |
|---|---|---|
| Tightening torque | 23-25 Nm | Be sure to use a torque wrench |
| Candle type | Iridium | The use of ordinary copper candles is prohibited |
| Electrode gap | 1.0 mm | Factory default setting |
| Resource | 45,000 - 60,000 km | Depends on fuel quality |
Also, do not ignore the condition of the ignition coils. If you notice signs of breakdown on the coil insulator or traces of carbon deposits inside its cap, you should replace it immediately. A new spark plug paired with a faulty coil will quickly fail. Checking the coils with a multimeter for winding resistance will help avoid repeated repairs.
The correct tightening torque and the use of iridium spark plugs are two main factors in the long operation of the ignition system on the Nissan Murano Z52.
Cost of work and need for service
If you are not confident in your abilities or do not have special equipment, it is better to entrust the work to professionals. On Nissan Murano Z52 Replacing spark plugs takes from 40 minutes to 1.5 hours, depending on the qualifications of the technician and the availability of the rear cylinders. The cost of work averages 2000-4000 rubles.
If you replace it yourself, you will save on labor costs, but will spend time searching for tools and purchasing spare parts. Weigh your skills before starting work.
- 💰 Savings: from 2000 to 4000 rubles (price of work)
- ⏱️ Time: 1-2 hours for independent replacement
- 🛠️ Tools: the need to purchase or rent special tools
If the car is under warranty, any independent tampering with the ignition system may result in refusal of warranty repairs. In this case, a visit to the dealer is required. However, for cars older than 3-4 years, replacing them yourself is an excellent opportunity to save money and control the quality of spare parts.
FAQ: Frequently asked questions
Is it possible to replace only one or two spark plugs if the others are in good condition?
No, you need to change the spark plugs as a set. They wear unevenly, but engine operation requires the same sparking conditions. Partial replacement will lead to imbalance and increased fuel consumption.
What to do if the spark plug won't come out?
Do not use excessive force. Try warming up the joint slightly using a hair dryer or warming up the engine if it is cold. Use a penetrating lubricant. If the spark plug still does not work, it is better to contact a specialist so as not to break the thread.
Do I need to change the ignition coils along with the spark plugs?
If the coils are working properly and have no external damage or signs of breakdown, it is not necessary to change them. However, with a mileage of more than 100,000 km, preventive replacement of the coils is recommended, since they often fail at the same time as the spark plugs.
Which spark plugs are better: original or Denso/NGK?
Original candles Nissan for Murano Z52 often produced in the same factories as the Denso or NGK brands. Therefore, high-quality analogues are quite suitable if they have the appropriate iridium electrode and the correct parameters.
How often should I check the gap on iridium spark plugs?
Iridium spark plugs have a fixed gap that does not require adjustment. However, when purchasing and before installation, it is recommended to visually check its compliance with the factory parameters (1.0 mm) to exclude defects.