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Maintenance

How to change spark plugs (DIY guide)

Replacing spark plugs is a satisfying DIY job that improves economy and smooth running.

📅 Aug 17, 2026 ✔ Free guide
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When to change them

Copper plugs: 20,000–30,000 km. Platinum: 60,000–80,000 km. Iridium: up to 100,000 km. Worn plugs cause rough idle, hesitation and higher consumption.

Step by step

  1. Work on a cold engine
  2. Remove the ignition coils or leads carefully
  3. Clean around each plug hole
  4. Remove old plugs one at a time (keep holes covered)
  5. Gap-check the new plugs against spec
  6. Hand-thread each plug — never force
  7. Torque to spec (typically 20–30 Nm)
  8. Refit coils/leads with a little dielectric grease

The golden rule

Never tighten a plug with a ratchet by feel in a cylinder head — the head is aluminum and strips easily. Use a torque wrench.

Questions about this guide

In an emergency, yes, but replace the whole set for even running and wear.
Stop — a seized plug in an aluminum head is risky. A tiny amount of penetrating oil and patience helps; otherwise let a professional handle it.
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