Parts for your 2002 Mitsubishi Pajero-Spark plugs

2002 Mitsubishi Pajero spark plugs

Quick verdict, backed by technical references: whether a 2002 Mitsubishi Pajero uses spark plugs depends on the engine. The petrol V6 models (commonly the 3.5L 6G74 in AU/NZ) use six spark plugs. The turbo‑diesel (3.2L Di‑D 4M41) doesn’t use spark plugs at all, it uses glow plugs and compression ignition. This split is confirmed by the Mitsubishi Pajero NM/NP Workshop Manual (Engine Electrical), the 2002 Owner’s Manual service schedule, and plug catalogues from NGK and DENSO listing spark plugs for the 6G7x petrol engines and glow plugs for the 4M41 diesel.

If it’s a diesel 3.2 Di‑D: spark plugs aren’t relevant because diesel fuel ignites from heat created by compression, not a spark. Those engines use glow plugs only for cold starting assistance.

If it’s a petrol V6: the spark plugs are key to how the Pajero starts, idles and pulls up hills. Each plug delivers a high‑energy spark inside the cylinder to ignite the air‑fuel mix, so worn plugs can mean hard starts, rough idle, sluggish performance and higher fuel use. The Pajero V6 runs six plugs, on many 6G74s the rear bank sits under the upper intake plenum, so factor in a new plenum gasket and a bit more labour when servicing. Technical references (Mitsubishi service literature and NGK/DENSO catalogues) specify long‑life platinum or iridium plugs for these engines, with a typical gap around 1.1 mm—always follow the under‑bonnet label and the plug maker’s spec.

For routine servicing, most owners stick with: replace iridium/platinum plugs about every 100,000 km, and inspect at 30,000–40,000 km if the vehicle sees lots of short trips, towing or dusty work. Copper plugs, if fitted, generally need changing much sooner. When fitting new plugs, start them by hand, tighten to the plug maker’s torque spec on a cold engine, and avoid anti‑seize unless the plug maker explicitly allows it (modern nickel‑plated threads don’t need it). A dab of dielectric grease inside the boots helps keep moisture out. If yours has ignition leads, check for cracking and resistance while you’re there, if it’s coil‑on‑plug, inspect the coil boots for tracking marks.

• Symptoms of tired plugs: hesitations under load, misfires, poor fuel economy, hard starting, and a sooty or glazed plug tip.
• Good practice: keep to quality iridium/platinum plugs from reputable brands, verify the heat range for the 6G74, and log the date/kilometres for the next service.

Technical sources consulted: Mitsubishi Pajero NM/NP Workshop Manual (Engine Electrical/Group 11), 2002 Pajero Owner’s Manual maintenance schedule, NGK and DENSO AU/NZ catalogues (spark plugs for 6G7x petrol, glow plugs for 4M41 diesel).

Popular questions

What spark plug type and gap suit a 2002 Pajero V6?
Quality iridium or platinum plugs specified for the 6G74 V6 are recommended by plug makers (for example, NGK and DENSO list long‑life options). The typical gap is around 1.1 mm, but always go with the under‑bonnet label or the plug manufacturer’s spec. Don’t open the gap on fine‑wire iridium/platinum plugs unless the maker says it’s OK.

How often should spark plugs be replaced?
For long‑life iridium/platinum plugs, plan on about 100,000 km. If the vehicle tows, does short trips or runs in dust, earlier inspection is smart. Copper plugs, if fitted, usually need changing at roughly 30,000–40,000 km.

Why doesn’t my 3.2 Di‑D diesel Pajero have spark plugs?
Diesels ignite fuel by compressing air until it’s hot enough to burn the injected diesel—no spark needed. They use glow plugs only to help with cold starts. That’s why “spark plugs” don’t apply to the 4M41 engine.