⚑Spark Plug Type

Infiniti I35 Spark Plug Type

Find the correct spark plug type, gap size, and replacement interval for your Infiniti I35. Covers all model years with torque specs.

Quick Answer

The Infiniti I35 typically uses iridium or platinum spark plugs. Newer models (2010+) use long-life iridium plugs rated for 60,000-100,000 miles. Check below for your specific year.

2002-2004

2002-2004
Spark Plug TypeCopper or Platinum
Plug Gap0.028" - 0.044" (0.7 - 1.1mm)
Replacement Interval30,000 miles
Torque Spec13 - 18 ft-lbs
Quantity4-8 (varies by engine)
Notes
  • β†’Use a torque wrench β€” over-tightened plugs can strip aluminum heads
  • β†’Apply a thin coat of anti-seize to threads (unless plug is pre-coated)

Frequently Asked Questions

What spark plugs does a Infiniti I35 use?
The Infiniti I35 spark plug type varies by year and engine. Newer models (2010+) typically use iridium plugs for longer service life. Older models may use platinum or copper. Check the specs below for your exact year.
How often should I change spark plugs on a Infiniti I35?
Modern Infiniti I35 models with iridium plugs can go 60,000-100,000 miles between changes. Older models with copper plugs need replacement every 30,000 miles. Replace sooner if you notice misfires, rough idle, or poor fuel economy.
What is the spark plug gap for a Infiniti I35?
Most Infiniti I35 models use a spark plug gap between 0.039" and 0.044" (1.0-1.1mm). Pre-gapped plugs from the OEM are recommended. Do not re-gap iridium-tip plugs as it can damage the electrode.
Can I upgrade to iridium spark plugs in my Infiniti I35?
Yes, upgrading from copper or platinum to iridium is generally safe and beneficial. Iridium plugs offer better ignitability, longer life, and improved fuel economy. Just match the correct heat range and gap for your engine.

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