Quick answer: Spark Plug Replacement (3.0T) on a 2014–2024 Infiniti Q50 is rated Moderate and takes about 2-3 hours. You'll need 10 tools for this job, and parts cost about $85. This guide walks you through the full job step by step, including the mistakes to avoid.
| Part Name |
Part Number |
Price |
Buy |
| NGK Iridium Spark Plugs Optional |
DF8H-11B (3.7L V6 2014-2015); 96008 / DILKAR8K8G (3.0T 2016+) |
$80.00 |
|
| Denso Iridium Spark Plugs |
3457 (FXE24HR11) |
$75.00 |
|
| Permatex Anti-Seize Lubricant |
80078 |
$5.00 |
|
| Permatex Dielectric Tune-Up Grease |
22058 |
$5.00 |
|
About prices: shown prices are typical retail averages and change frequently; cheaper alternatives may be available. Confirm the current price before buying.
💡 Pro tip: Order all parts at once to save on shipping
Step-by-Step Instructions
Follow these steps carefully
1
Cool the engine
The Infiniti Q50 3.0T (VR30 twin-turbo V6) uses NGK DILKAR8K8G (NGK 96008) iridium plugs. Gap: 0.031" — this is a tight turbo gap (not the 0.044" of a naturally aspirated engine). Do not use the wrong gap — the twin-turbo needs the tight 0.031". Torque: not verified — check the service manual (do not guess). You'll need: 6x NGK DILKAR8K8G, spark plug socket, extensions. Critical: let the twin-turbo engine cool completely — the turbos retain heat. The VR30's engine bay is TIGHT — the twin turbos crowd the plugs. Expect a fiddly job. Never work on a hot turbo engine.
🔧 Mechanic's note — Tom Becker
I'm Tom Becker. Do not skip the cooldown — I once pulled a plug an hour after shutdown on a twin-turbo and the threads were still hot enough to gall. Give the VR30 a full cold-soak; your aluminum heads will thank you.
2
Access the ignition coils
Remove the engine cover. The VR30's twin turbos make the engine bay very tight — the coils are buried. You may need to remove intake piping, brackets, or other components to access the coils. Take photos before disconnecting anything — the turbo plumbing is complex.
3
Remove one coil at a time
Remove ONE coil at a time. Unplug the connector, unbolt the coil, pull it straight out. The VR30's coil boots see high heat from the turbos — inspect for brittleness or cracking. Don't mix up the coils.
4
Remove the old spark plug
The 0.031" gap is critical for the twin-turbo — if the old plugs were gapped wider, that's a problem. The tight bay makes plug removal fiddly — use extensions and a universal joint. Don't drop anything into the open holes.
5
Gap and hand-thread the new plug
The new NGK DILKAR8K8G comes pre-gapped at 0.031" — verify with a wire gauge but DO NOT adjust. The tight 0.031" gap is essential for the twin-turbo's high boost — a wider gap causes misfire under boost. Hand-thread the new plug until it seats.
6
Torque to specification
Torque to Infiniti spec — not verified for the VR30, so check your service manual. The twin-turbo's high cylinder pressures demand correct plug torque — loose plugs blow out, over-tight strips the head. Use a torque wrench.
7
Reinstall the coil
Reinstall the coil — seat it firmly, bolt it down, reconnect the connector. Reinstall any intake piping, brackets, or components you removed for access. Double-check all turbo plumbing connections — a boost leak causes drivability issues. Ensure every coil connector is clicked.
8
Reassemble and test
Reinstall the engine cover. Start the engine — the VR30 should idle smoothly. Check for misfire codes (P0300-P0306). The Q50 3.0T's twin-turbo needs the tight 0.031" gap — if you have misfires under boost, recheck the gaps. Test drive: the VR30 should pull hard with no stutter. The tight engine bay makes this a patience job — but the NGK DILKAR8K8G at 0.031" is the correct setup. Don't use a wider gap or non-iridium plugs — the twin-turbo will misfire.
All Done!
Test your repair before closing everything up. If something doesn't work right, double-check your steps.
⚠️ Common Mistakes to Avoid
- • Not properly gapping the new spark plugs
- • Over-tightening the spark plugs
- • Failing to use anti-seize lubricant on threads
- • Not properly reconnecting ignition coils
- • Neglecting to clear error codes after replacement
