Nissan Sunny FB15 is a legendary car that is still popular today due to its reliability and ease of maintenance. However, even such time-tested machines have weak points, and one of them is spark plugs. Not only the stability of the engine depends on their condition GA15DE, but also fuel consumption, acceleration dynamics, and in some cases even the service life of the catalyst.

In this article we will look at everything the owner needs to know. Sunny FB15 about spark plugs: from original articles and high-quality analogues to step-by-step replacement instructions. We will pay special attention to typical mistakes that are made during selection and installation, as well as signs indicating the need for urgent replacement. If your engine starts to stall, vibration appears at idle, or gasoline consumption increases, this information will help save time and money on diagnostics.

Which spark plugs are suitable for Nissan Sunny FB15 (GA15DE)

Engine GA15DE, installed on Nissan Sunny FB15 (1990–1999), requires candles with specific parameters. Original parts from Nissan have an article number 22401-4M000 (or 22401-4M005 for some modifications), but there are many high-quality analogues on the market. The main thing is to comply heat number 5–6 and carving M14×1.25 with thread length 19 mm.

Among the trusted brands:

  • 🔧 NGK — BPR5ES-11 (the most popular analogue, corresponds to the original in all respects).
  • 🔧 Denso — W16EP-U (improved insulation alternative).
  • 🔧 Bosch — WR7DC (suitable for gas equipment if the car is converted to LPG).
  • 🔧 Champion — RC9YC (budget option, but with a reduced resource).

Important: if your Sunny FB15 operated on gas, it is recommended to choose candles with reduced clearance (0.7–0.8 mm instead of the standard 0.9–1.0 mm) or specialized models for HBO, for example, NGK LPG2 or Denso IW16.

📊 What spark plugs do you use in your Nissan Sunny FB15?
  • Original Nissan
  • NGK BPR5ES-11
  • Denso W16EP-U
  • Bosch or other brand
  • I don't know which ones are worth

Signs of faulty spark plugs

Spark plugs in Nissan Sunny FB15 rarely fail suddenly - problems usually accumulate gradually. If you ignore the first symptoms, it can lead to misfires, increased load on the coils and even damage to the catalytic converter. Look out for the following signs:

  • ⚡ Engine tripping - especially noticeable at idle or when pressing the gas sharply.
  • ⛽ Increased fuel consumption (more than 9–10 l/100 km in the city with a working engine).
  • 🚗 Dips during acceleration — the car “stumbles” when overtaking or going uphill.
  • 🔥 Black or white soot on the electrodes (visible upon visual inspection).
  • 💨 The smell of gasoline from the exhaust pipe - indicates incomplete combustion of fuel.

Critical point: if cracks in the insulator or melted electrodes are found on the spark plugs, they must be replaced immediately - this is a sign of detonation or overheating, which can damage the pistons.

⚠️ Attention! On Sunny FB15 with a mileage of more than 150 thousand km, misfires can be caused not only by spark plugs, but also worn high-voltage wires or coils. Before replacing spark plugs, check the resistance of the wires (should be between 5–10 kOhm).

When to change spark plugs on Nissan Sunny FB15

The manufacturer recommends replacing spark plugs every 30–40 thousand km, but this interval is relevant only for original parts or high-quality analogues (NGK, Denso). Cheap candles (for example, Champion RC9YC) can fail after 20 thousand km, especially when driving aggressively or using low-octane gasoline.

Factors that reduce spark plug life:

  • 🛢️ Bad fuel (impurities, low octane number).
  • 🔥 Engine overheating (for example due to a faulty thermostat).
  • 💨 Oil soot (oil enters the combustion chamber through the valve stem seals).
  • ⚡ Faulty coils or wires (lead to breakdowns and erosion of electrodes).

If you are using gas equipment, spark plugs wear out faster due to higher combustion temperatures. In this case, the replacement interval is reduced to 20–25 thousand km.

How to check spark plugs without removing them?

If you don’t have time for dismantling, you can perform express diagnostics:

1. Start the engine in the dark and look at the high-voltage wires - if there are breakdowns, sparks will be visible.

2. Disconnect the wires from the spark plugs one by one (with the engine running). If the engine sound does not change when switched off, the spark plug is faulty.

⚠️ Be careful: wear dielectric gloves to avoid electric shock.

Step-by-step instructions for replacing spark plugs

Replacing spark plugs with Nissan Sunny FB15 does not require special skills, but there are nuances that will help you avoid mistakes. You will need:

  • 🔧 Candle key on 16 mm (preferably with a rubber bushing to secure the spark plug).
  • 🔧 Extension and ratchet handle.
  • 🔧 Compressor or compressed air cylinder (for cleaning wells).
  • 🔧 Dielectric grease (optional, to prevent sticking).

Procedure:

  1. Disconnect the negative terminal of the battery (required!).
  2. Remove the high voltage wires by pulling on the caps (do not pull on the wire itself!).
  3. Blow out the spark plug wells with compressed air to prevent dirt from getting into the cylinders.
  4. Unscrew the old spark plugs counterclockwise. If the candle “sticks”, do not use excessive force - use penetrating lubricant (For example, WD-40) and let stand for 10-15 minutes.
  5. Install new spark plugs by screwing them in by hand until it stops, then tighten with the wrench 20–25 Nm (do not overtighten!).
  6. Connect the high voltage wires in order 1-3-4-2 (cylinder numbering is from the timing side).

Disconnected battery terminal|Cleared the spark plug wells from dirt|Checked new spark plugs for defects|Have a torque wrench at hand (or experience tightening it “by feel”)|High-voltage wires are marked for correct connection-->

⚠️ Attention! If you hear a crunching sound when unscrewing the spark plug or it is tight, don't use force - you risk breaking the threads in the block head. In this case, repairs will be required with the installation of a screw, which will cost 5–10 thousand rubles.

Typical mistakes when replacing spark plugs and how to avoid them

Even experienced car owners sometimes make mistakes that lead to serious consequences. Here are the most common:

Error Consequences How to avoid
Re-upholstery of candles Thread failure in cylinder head, repair with engine disassembly Use a torque wrench (20–25 Nm)
Insufficient tightening Misfire, spark plug overheating, failure Tighten by hand until it stops, then tighten with a wrench
Using spark plugs with the wrong heat rating Detonation (too hot) or misfire (too cold) Check markings: for GA15DE suitable heat number 5–6
Dirt getting into the cylinders Scoring on cylinder walls, accelerated wear of piston rings Blow out the wells with compressed air before removing the spark plugs

Another common problem is confusion with high voltage wires. If you connect them in the wrong order, the engine will run erratically or won't start at all. On Sunny FB15 connection procedure (account from the timing side): 1st cylinder → 3rd → 4th → 2nd.

💡

Before installing new spark plugs, apply a thin layer dielectric grease on the thread - this will prevent sticking and make the next replacement easier. Do not use regular graphite or lithol - they may cause overheating!

Spark plugs for tuned Nissan Sunny FB15

If your Sunny FB15 modified (installed turbocharger, compression ratio is changed or used direct injection), standard candles may not be suitable. In such cases, parts with:

  • 🔥 Colder heat rating (7–8 for turbo engines).
  • ⚡ Reduced clearance (0.6–0.7 mm for boosted engines).
  • 🛡️ Reinforced insulation (For example, NGK Iridium IX or Denso Iridium Power).

For engines with DOHC gas distribution mechanism (found on some versions FB15) candles with platinum or iridium electrodes, since they maintain a stable spark longer at high speeds. Examples:

  • 🔧 NGK IFR5A11 (iridium, resource up to 100 thousand km).
  • 🔧 Denso IK16 (universal option for tuned engines).

Critical recommendation: If you increase the compression ratio (for example, by boring the block or installing a forged piston), be sure to use plugs with a heat rating 1-2 units cooler than standard. Otherwise, you run the risk of detonation and destruction of the pistons.

Where to buy spark plugs for Nissan Sunny FB15 and how much do they cost?

Spark plug prices vary depending on the brand and type of electrode. The table below shows current offers (for 2026) for Sunny FB15:

Brand and article Type Average price per piece, ₽ Where to buy
NGK BPR5ES-11 Nickel, standard 250–350 Exist, Autodoc, local stores
Denso W16EP-U Nickel, improved insulation 300–400 Wildberries, Ozon, specialized auto sites
Bosch WR7DC For HBO 280–380 Gas services, AutoSpetsCenter
NGK IFR5A11 Iridium, long life 800–1200 Official dealers, large online stores

When purchasing, pay attention to:

  • 📦 Packaging — original candles NGK or Denso always in branded boxes with a hologram.
  • 🔍 Marking — the electrode must have an engraving of the article number.
  • 🛒 Place of purchase — avoid spontaneous markets and dubious online sites.

If you doubt the authenticity, compare the weight of the candle with the original - fakes are often 10-15 grams lighter due to the use of cheap materials.

💡

Saving on spark plugs is more expensive: cheap analogues can cause misfires, which will lead to failure of the catalyst (the price of a new one is from 15 thousand rubles).

FAQ: Frequently asked questions about spark plugs for Nissan Sunny FB15

Is it possible to use platinum or iridium spark plugs instead of standard ones?

Yes, but only if they match the heat rating and geometry. Iridium spark plugs (eg NGK IFR5A11) last longer (up to 100 thousand km), but their high price is justified only with a large annual mileage. For most owners Sunny FB15 sufficiently high-quality nickel spark plugs (NGK BPR5ES-11).

What happens if you don't change spark plugs on time?

The consequences depend on the degree of wear:

  • At the initial stage - increased fuel consumption and loss of power.
  • With severe wear, misfires can occur, which can damage the catalyst.
  • In critical cases - detonation leading to destruction of pistons or valves.

On Sunny FB15 with a mileage of more than 200 thousand km, worn spark plugs also accelerate failure ignition coils.

What gap should be on the spark plugs for GA15DE?

Standard clearance for gasoline engines GA15DE — 0.9–1.0 mm. If the car runs on gas, the gap is reduced to 0.7–0.8 mm. Check the gap round probe, and not flat - this is more accurate.

Is it possible to clean spark plugs instead of replacing them?

Mechanical cleaning (for example, with a wire brush) is not recommended - it damages the protective coating of the electrodes. Acceptable only ultrasonic cleaning or treatment with special means (for example, Liqui Moly Ventil Sauber), but this is a temporary measure. If the spark plugs have worked for more than 30 thousand km, it is better to replace them.

Why does the engine run worse after replacing spark plugs?

Possible reasons:

  • Incorrect clearance or heat rating.
  • Confusion with high voltage wires (check the connection order!).
  • Defective candles (especially if you bought cheap analogues).
  • Dirt getting into the cylinders during replacement.

If the problem persists, check compression And condition of high-voltage wires.