Car Nissan Primera P12 deservedly considered one of the most reliable sedans and hatchbacks in its class. However, even such a technically advanced unit has components that require regular attention. The key element of the ignition system, which directly affects the dynamics, fuel consumption and smooth operation of the engine, are the spark plugs.
Many owners are faced with a problem: as soon as the mileage exceeds 60-80 thousand kilometers, the engine begins to stall, and starting in cold weather becomes difficult. Often this is not a sign of a serious breakdown, but a signal that the spark plug electrode has exhausted its service life. Correct selection and timely replacement of consumables will return to your Primera former agility and efficiency.
Features of the ignition system of QR and SR series engines
Under the hood Nissan Primera P12 The most common petrol engines are 1.6, 1.8 and 2.0 liters. These units belong to the family QR (for example, QR18DE or QR20DE), less often - to the family SR. The design of these engines involves the use of ignition coils mounted directly on each spark plug. This solution eliminates high-voltage wires, which often become a source of energy losses and breakdowns.
It is important to understand that the design of the combustion chamber and the shape of the pistons in engines QR requires strict adherence to the thermal range of candles. If you install an element with the wrong heat rating, the engine may detonate or, conversely, quickly become covered with soot. Therefore, when choosing, you need to focus on the factory specifications, and not on the advice of your neighbors in the garage.
A special feature of the system is the absence of an ignition distributor (distributor). This means that each spark plug operates in its own individual cycle, controlled by an electronic unit. A malfunction of one element affects the balance of the entire cylinder, which is immediately felt by vibrations of the steering wheel and twitching of the body during acceleration.
Original articles and cross-references
When ordering spare parts for Nissan Confusion often arises due to the large number of modifications. For standard 1.8 and 2.0 liter engines, the most relevant is the original article number 22401-ED000. These are nickel spark plugs that last about 40-50 thousand kilometers with quiet driving. However, engines with CVTC variable valve timing often require iridium-coated spark plugs, which have a different part number.
If you are looking for more durable analogues, pay attention to brand products NGK And Denso. It is these manufacturers who supply the conveyor. For Primera P12 models fit perfectly NGK BKR6E-11 or their iridium versions NGK SILZKAR7B11. The use of high-quality analogues allows you to increase the service replacement interval to 80-100 thousand kilometers.
Below is a table with the main part numbers for various engine modifications so that you can choose the appropriate option:
| Engine | Volume (l) | Original article | Analogue (NGK) | Analogue (Denso) |
|---|---|---|---|---|
| QR18DE | 1.8 | 22401-ED000 | 4355 (BKR6E-11) | 2451 (K20PR-U11) |
| QR20DE | 2.0 | 22401-ED000 | 4355 (BKR6E-11) | 2451 (K20PR-U11) |
| SR18DE | 1.8 | 22401-31U00 | 4355 (BKR6E-11) | 2451 (K20PR-U11) |
| QR20DE (Iridium) | 2.0 | 22401-AX000 | 6418 (ILZKAR7B11) | 3443 (IK20) |
⚠️ Attention! Do not try to save money by buying “no-name” candles with dubious markings. In engines Nissan With a CVTC system, a bad spark can lead to malfunctions of the camshafts, the repair of which will cost much more than a set of quality spark plugs.
Symptoms of wear and troubleshooting
How do you know when it's time to change elements? The most obvious sign is unstable engine idle. If the tachometer needle fluctuates smoothly, and interruptions (“farts”) are heard from the exhaust pipe, most likely one or more cylinders are not working properly. This is a classic symptom of “triple” caused by breakdown of the insulator or burnout of the central electrode.
Another warning sign is increased fuel consumption. When a misfire occurs, the mixture does not burn completely, going into the exhaust system, where it simply heats the air and the catalytic converter. The electronic control unit tries to compensate for the loss of power by supplying more fuel, which leads to excessive consumption. Also pay attention to the difficulty of cold starting, especially in winter.
Visual inspection is the best diagnostic method. If you remove the old spark plugs and see black dry carbon deposits, this indicates an over-rich mixture or problems with the crankcase ventilation system. If the carbon deposits are oily and black, the oil seals or piston rings may be worn out. A bronze or reddish coating often indicates the use of low-quality fuel with a large amount of additives.
- 40-50 thousand km
- 80-100 thousand km
- 120+ thousand km
- I don't change it until it breaks
Step-by-step instructions for replacing spark plugs
Replacement process Nissan Primera P12 relatively simple, but requires care. First you need to open the hood and remove the plastic decorative engine cover, if installed. On series motors QR Access to the spark plugs is through separate ignition coils, which are bolted to the cylinder head.
Before starting work, be sure to disconnect the negative terminal of the battery to avoid a short circuit or accidental starting of the engine. Remove the electrical connectors from the ignition coils by pressing the latch. Then unscrew the coil mounting bolts (usually 10mm socket head bolts) and carefully remove them. If the coil gets stuck, do not use excessive force, it is better to slightly rock it from side to side.
To unscrew the spark plugs, use a spark plug wrench with an extension and a universal joint. It is important to observe the tightening torque so as not to strip the threads in the aluminum cylinder head. If you don't have a torque wrench, screw the spark plug all the way in, then tighten it 1/2 or 2/3 turn for the rubber gasket. For iridium spark plugs with a thin electrode, the tightening torque is critical; they should not be overtightened.
☑️ Preparation and replacement of candles
After installing the new elements, reassemble everything in reverse order. Make sure that all connectors are clicked into place. If this is not done, the engine will run intermittently. Start the engine and listen carefully to its operation. The vibration should disappear, and the sound of operation should become smooth and monotonous.
⚠️ Attention! Always use a spark plug wrench with a rubber magnet inside. Without it, you risk dropping the spark plug into a deep well, from where removing it will turn into a serious problem requiring removal of the valve cover.
Why can ignition coils fail?
A common cause of problems is not only wear of the spark plugs, but also failure of the coils themselves. On Nissan P12 cars, the coils often overheat due to poor ventilation or a short circuit inside. If the problem persists after replacing the spark plugs, check the resistance of the coils with a multimeter or swap them to locate the faulty cylinder.
Typical maintenance errors
One of the most common mistakes is ignoring the condition of the ignition coils. If you change spark plugs after a mileage of more than 100 thousand kilometers, the old coils may not provide enough voltage to break the gap on the new spark plug. This will cause new spark plugs to quickly fail or not provide the required power. It is recommended to inspect the coils for cracks and signs of breakdown.
Another mistake is incorrectly adjusting the gap. Although modern spark plugs often have a non-adjustable gap, some models allow you to bend it. Do not attempt to adjust the gap on iridium electrodes as they are very fragile and break easily. For nickel spark plugs, the gap must strictly comply with technical regulations (usually 1.0–1.1 mm for Nissan), otherwise either a missed spark or premature wear will occur.
Never use sealants or lubricants on the threaded part of the spark plug unless instructed to do so. In engines Nissan With an aluminum cylinder head, the threads can become damaged if the spark plug seizes due to improper lubrication. If the thread is damaged, the only solution is to install bushing inserts, which requires complex repairs.
Before installing a new spark plug, apply a drop of graphite lubricant to the threads to ensure easy removal next time. This is especially true for cars operated in conditions of frequent temperature changes.
Effect of fuel on spark plug life
The quality of gasoline directly affects the service life of spark plugs. Engines Nissan Primera quite sensitive to octane number and the presence of impurities. Using low octane fuel (for example, A-80 instead of A-92) causes detonation, which destroys the insulator and electrodes of the spark plugs.
Fuel additives, especially those containing lead or other metals, can form deposits on the electrodes. These deposits create a conductive layer through which the spark goes to ground without burning fuel. As a result, the candle stops working, even if visually it looks clean. The use of low-quality fuel is the main reason for the failure of the ignition system on Nissan cars in regions with a poor gas station network.
To extend the life of spark plugs, it is recommended to periodically (every 15-20 thousand km) clean the fuel system or use high-quality detergent additives. This will help reduce carbon deposits and keep the injectors clean, which together will ensure optimal combustion of the mixture.
Regularly replacing spark plugs and monitoring the condition of the ignition coils is the key to stable engine operation and no starting problems in any season of the year.
FAQ: Frequently asked questions
How many spark plugs are needed for Nissan Primera P12?
Engine as standard Nissan Primera P12 has 4 cylinders, so a complete replacement requires exactly 4 spark plugs. If you have a modification with a turbocharger or another volume, the quantity may differ, but for most civilian versions it is 4 pieces.
Is it possible to use iridium spark plugs instead of nickel spark plugs?
Yes, iridium spark plugs (eg NGK ILZKAR7B11) are an excellent replacement for standard nickel ones. They have a long service life (up to 100 thousand km) and provide a more stable spark. The main thing is to make sure that the heat rating and thread size match the original requirements.
What to do if the spark plug is stuck in the block head?
If the spark plug is stuck, do not try to unscrew it “cold” with great force. It is better to warm up the engine to operating temperature, as the metal will expand and the threads will become more pliable. Use a penetrating lubricant (WD-40 or similar) and gently wiggle the spark plug, gradually increasing the twist angle.
How often do you need to change spark plugs on a QR20DE engine?
For standard nickel spark plugs, the replacement interval is 40-50 thousand kilometers. If you use iridium analogs, the service life increases to 80-100 thousand kilometers. However, it is recommended to check their condition at every maintenance.