BDFHYK UF550 ignition coil and 1406 / DILKAR7B11 spark plug kit

6 UF550 ignition coils and 6 Laser Iridium spark plugs

UF550 ignition coil pack with 1406 / DILKAR7B11 spark plugs

BDFHYK OE-style UF550 ignition coil replacement set

UF550 coil-on-plug components with 1406 / DILKAR7B11 spark plugs

Ignition service kit with UF550 coils and 1406 / DILKAR7B11 plugs

BDFHYK UF550 and 1406 / DILKAR7B11 ignition service components

BDFHYK Ignition Coil Pack UF550, Fits Nissan Altima Maxima Murano Pathfinder Quest Infiniti EX35 FX35 Q50 2.5L 3.5L V6, Set of 6

$79.99

Type Ignition Coil + Spark Plug Set
SKU BDDLZ-BD-05-07074BK
OE Number For Coil: ?UF550, C1670, 22448-JA10C, 5C1727, E1050, 52-2082, IC630, 1788376, 522082, 6734029, 22448-JA11C, 22448-JA10A, IGC0003, 50150
OE Number For Spark plug:1406, 224011LA1C, 22401-1LA1C, DILKAR7B11, 7805-3382-7810-3302-06

Trust & Assurance

Free Shipping · 3–7 Business Days

12-Month Warranty

30-Day Return

Secured Payment

Technical Specifications

Brand	BDFHYK
Product Type	Ignition Coil + Spark Plug Kit
Primary Coil Reference	UF550
Spark Plug Reference	1406 / DILKAR7B11
Spark Plug Construction	Laser Iridium
Package Quantity	6 Ignition Coils + 6 Spark Plugs
Includes	6 Ignition Coils + 6 Laser Iridium Spark Plugs
Listed Vehicle Fitment	Nissan 350Z / Altima / Maxima / Murano / Pathfinder / Quest — listed 3.5L V6 applications; INFINITI G35 / FX35 / JX35 / QX60 and related listed 3.5L V6 applications
OE / Interchange References	UF550, C1670, 22448-JA10C, 5C1727, E1050, 52-2082, IC630, 1788376, 22448-JA11C, 22448-JA10A, IGC0003
Inspection Guidance	No universal ignition-coil replacement interval. Inspect during spark-plug service, around higher-mileage service such as roughly 60,000–100,000+ miles when history is unknown, or sooner if misfire, rough idle, hard starting, hesitation, oil/moisture contamination, or connector damage is present.
Common Service Scenarios	Cold-start misfire, rough idle, hesitation under load, cylinder-specific misfire, spark-plug service, and high-mileage ignition inspection after diagnosis.
Fitment Checks	Confirm exact year, model, engine, connector shape/keying, coil body, boot profile, coil reference, spark plug reference, and required service quantity.
Installation Checks	Inspect wiring, connectors and plug wells; compare new components with removed parts; follow exact vehicle spark plug gap and tightening-torque specifications.
Important Note	This kit is intended for the listed 3.5L V6 applications. Do not select it for a 2.5L hybrid application unless the original ignition coil and spark plug references are confirmed to match.

UF550 Ignition Coil & 1406 Laser Iridium Spark Plug Kit for Nissan / INFINITI 3.5L V6

Cold-start shaking, rough idle, hard starting, or hesitation under acceleration can involve worn ignition components, but similar symptoms may also come from wiring, injectors, fuel delivery, intake leaks, sensors, compression, or mechanical faults. This BDFHYK UF550 ignition service kit is intended for the listed applications below. Confirm the exact vehicle, engine, connector, spark plug reference, and service quantity before ordering.

UF550 / 1406 / DILKAR7B11 Vehicle Fitment

Nissan 350Z / Altima / Maxima / Murano / Pathfinder / Quest — listed 3.5L V6 applications
INFINITI G35 / FX35 / JX35 / QX60 and related listed 3.5L V6 applications

What Is Included?

6 ignition coils
6 Laser Iridium spark plugs

Fitment note: This kit is intended for the listed 3.5L V6 applications. Do not select it for a 2.5L hybrid application unless the original ignition coil and spark plug references are confirmed to match.

UF550 Ignition Coil Reference Numbers

UF550, C1670, 22448-JA10C, 5C1727, E1050, 52-2082, IC630, 1788376, 22448-JA11C, 22448-JA10A, IGC0003

When Should You Inspect the Ignition Coils?

Ignition coils do not have one universal mileage-based replacement interval. Inspect them when spark plug service is due, when an older vehicle reaches higher-mileage service, or when symptoms appear. If service history is unknown, roughly 60,000–100,000+ miles is a useful inspection window for coil boots, connectors, plug wells, spark plug wear, and stored misfire codes—not an automatic replacement point.

Frequent short trips, stop-and-go driving, high-load use, long idling, repeated heat cycles, or oil and moisture in the plug wells can justify earlier inspection. Worn spark plugs can also increase voltage demand on the ignition coils.

What May Improve After Replacing a Confirmed Weak Coil or Worn Plug?

More stable idle if weak spark was causing rough running
More consistent starting if ignition energy had become marginal
Smoother acceleration or load response if misfire was ignition-related
Fewer cylinder-specific misfire events after the actual failed component is corrected

These are restoration benefits, not a promise of extra horsepower or guaranteed fuel-economy gains.

High-Mileage Ignition Service Scenarios

Spark Plug Service Is Due

Inspect the coils while the plugs are being serviced for cracked housings, carbon tracking, damaged boots, loose connectors, oil contamination, or moisture. Replace coils when testing or physical condition supports replacement rather than replacing them by mileage alone.

Cold-Start Shaking or Rough Idle

Check cylinder-specific misfire codes and inspect the plug and coil on the affected cylinder. A flashing check-engine light can indicate an active misfire and should be addressed promptly.

Hesitation Under Acceleration or Load

A marginal coil or worn plug may become more noticeable as cylinder pressure rises under acceleration. Confirm the affected cylinder and component condition before replacement.

Fitment & Installation Checks

Match the exact year, make, model, engine, and cylinder configuration.
Compare connector keying, coil body, mounting point, boot profile, and printed reference numbers.
Confirm spark plug reference 1406 / DILKAR7B11 for the exact engine.
Follow the exact vehicle service specification for spark plug gap and tightening torque.
Inspect wiring, connectors, boots, and plug wells for oil, moisture, corrosion, or physical damage.

Important: These are BDFHYK OE-style aftermarket ignition service components, not factory-branded parts. A diagnostic trouble code alone does not prove that an ignition coil has failed.

Difficulty Moderate

Estimated Time 0.5–1 hour

Tools Required

Screwdrivers
Service manual specific to your vehicle
Socket set and ratchet
Wrenches

Pre-Installation Checklist

Stop the engine before disassembling or replacing the ignition coil.
Check the spark plugs and spark plug wires as part of diagnosis.
Keep the installation area clean and dry.
Make sure the ignition coil connections are correct.
Refer to the service manual for your specific vehicle because removal order and connector or fastener details can vary by make and model.
Disconnect the negative battery cable before working on the ignition system.

Installation Steps

Disconnect the battery. Remove the negative battery cable by loosening the clamp bolt with a socket or wrench.
Locate the ignition coils on top of the engine. They may be attached to the engine block or surrounding components.
Disconnect and remove the old ignition coil. Remove the mounting bolts or screws and disconnect the electrical connector(s). The order can vary by vehicle, so follow the vehicle-specific service manual. Remove the old coil once fully disconnected.
If one coil serves multiple spark plugs and has multiple electrical connections, mark or label the connectors so they can be reattached to the correct terminals.
Install the new ignition coil in the reverse order of removal. Secure the mounting bolts or screws and reconnect the electrical connector(s) in the correct positions.
Reconnect the negative battery terminal. Hand-tighten the connection, then tighten the terminal bolt with a socket or wrench. Do not over-tighten.
Close the hood, start the engine with the vehicle in Park, and confirm it starts and idles normally. If it does, test-drive the vehicle.

Post-Installation Verification

Confirm the new ignition coil is securely mounted.
Confirm all electrical connectors are connected to the correct terminals.
Confirm the negative battery terminal is reconnected and tightened sufficiently without over-tightening.
Start the engine in Park and confirm it starts and idles normally.
If idle is normal, test-drive the vehicle and check for remaining misfire or drivability symptoms.

Troubleshooting

Spark plug and wire checks from the manual:
With the engine running, disconnect spark plug wires one at a time and observe engine-speed or roughness changes; the manual states that no significant change can indicate a bad spark plug.
The manual describes checking for spark by holding the end of a disconnected spark plug wire near a metal surface and looking or listening for a spark or cracking sound.
While the engine is cranked, check for spark at each spark plug wire; the manual states that no spark can indicate a dead wire.
Make sure battery, ignition, coil, and spark-plug wire connections are secure. Wiggle connections and retest if a loose connection is suspected.
Keep spark plug ends clean and free of dirt, oil, or grease; clean and retest before replacing a plug.
Inspect wires for cracked, cut, scraped, or burned insulation. Check boots and terminals for damage, corrosion, or poor contact.
Check for corrosion between the boot, spark plug, and ignition coil, and inspect the spark plug for discoloration or damage.
Inspect spring clips and wire retention at the distributor and spark plug ends to make sure connections are held securely.
Ignition coil failure can cause one or more cylinders to misfire, stuttering, sluggishness, and other drivability issues.

BDFHYK Ignition Coil Installation Guide

Q: What is included in this UF550 ignition kit?
A: The package includes 6 ignition coils and 6 Laser Iridium spark plugs.

Q: Which vehicles does this kit fit?
A: Use the listed applications as a starting point, then confirm the exact year, model, engine, connector and original part references before ordering.

Q: At what mileage should ignition coils be inspected?
A: There is no universal replacement mileage. On older vehicles, roughly 60,000–100,000+ miles is a useful inspection window when service history is unknown, but coils should be replaced based on diagnosis and condition rather than mileage alone.

Q: Should ignition coils automatically be replaced at 100,000 miles?
A: No. If the engine runs correctly and the coils test well, mileage alone is not a reason to replace them. Inspect them during spark-plug service and replace failed or physically damaged coils as needed.

Q: Can worn spark plugs increase stress on ignition coils?
A: Yes. As the firing gap becomes harder to bridge, ignition voltage demand can increase. Keeping spark plugs on the correct service schedule can reduce unnecessary stress on the coils.

Q: Can weak coils cause rough idle or hesitation?
A: They can contribute to rough idle, cold-start shaking, hesitation under load, and cylinder-specific misfires. Other fuel, air, electrical, sensor, or mechanical faults can cause similar symptoms.

Q: What can improve after replacing a confirmed weak coil or worn plug?
A: When the ignition components were the cause, the engine may return to a steadier idle, more consistent starting and smoother acceleration. Replacement restores lost ignition performance; it does not create extra rated horsepower.

Q: Should coils and spark plugs always be replaced together?
A: Not automatically. Inspect both systems together and service according to actual condition, maintenance history and package quantity.

Q: What does a flashing check-engine light mean?
A: A flashing check-engine light can indicate an active misfire. Reduce driving and diagnose the fault promptly because continued misfiring can overheat the catalytic converter.

Q: What should be checked before installation?
A: Confirm fitment, compare the connector and coil shape, inspect plug wells for oil or moisture, and use the exact service specification for spark plug gap and tightening torque.

Q: What if the engine still misfires after replacement?
A: Continue diagnosis of wiring, connectors, injectors, fuel pressure or delivery, intake or vacuum leaks, sensors, compression and mechanical timing instead of replacing more parts at random.

Returns & Refunds

We accept returns within 30 days of delivery for eligible items. If the product is unused and in original condition, you may request a return according to our refund policy. Full policy details: View Refund Policy . We recommend contacting our support team before initiating a return to ensure the fastest resolution.

Customer Support

If you purchased the wrong part, received an incompatible item, or need installation assistance, please contact us directly.

Email: service@bdfhyk.com

Business Hours:

Mon–Fri 9:00–18:00 (GMT+8)

Mon–Fri 19:00–04:00 (UTC−6 / CST)

Manufacturing Standards

Direct Factory Supply, Cost Saving
Integrated R&D, production, and warehousing. Eliminate middleman markups: same quality at lower prices, superior quality at same prices.

Precision Inspection, Commitment to Excellence
Rigorous inspection process, international certification standards. Each product includes individual inspection.

Before vs After Replacement

Replacing worn ignition coils and spark plugs helps restore stable ignition and smoother engine performance.

BEFORE

Rough Idle & Engine Vibration Noticeable engine shaking while idling. Irregular exhaust flow may indicate unstable ignition performance.

AFTER

Fast Start & Stable Idle IMore consistent spark delivery reduces misfires and stabilizes idle speed.

BEFORE

Sluggish Acceleration Weak throttle response at lower RPM. Vehicle may feel underpowered.

AFTER

Enhanced Power Response Improved throttle response and smoother acceleration

BEFORE

Increased Fuel Consumption Poor combustion can lead to higher fuel usage.

AFTER

Improved Fuel Efficiency Optimized ignition supports more efficient combustion.

Performance improvements may vary depending on vehicle condition.