Parts for your 2010 Mitsubishi Lancer-Ignition coils

2010 Mitsubishi Lancer ignition coils — what they do and when to replace

Based on Mitsubishi’s 2008–2015 Lancer Factory Service Manual (Engine Electrical), the Mitsubishi ASA electronic parts catalogue, and aftermarket catalogues from Denso and NGK, the 2010 Lancer petrol engines (4B10 1.8L, 4B11 2.0L, 4B12 2.4L and 4B11T turbo) all use coil-on-plug ignition coils, one per cylinder. If the vehicle is a diesel variant (such as the 1.8 Di-D offered in some markets), it won’t have ignition coils at all, because diesels ignite fuel by compression rather than spark.

For petrol models, the ignition coils are the quiet achievers that turn the battery’s low voltage into the high-voltage punch needed to jump the spark plug gap. On the 2010 Lancer they sit directly on top of each spark plug, which keeps the spark strong and timing accurate, helps cold starts, and trims emissions.

There’s no fixed replacement interval in the factory schedule for coils, they’re serviced on condition. During regular servicing (every 10,000–15,000 km in typical AU/NZ schedules), it’s worth checking for coil-related hints: rough idle, sluggish acceleration, higher fuel use, a flashing MIL, or a distinct misfire under load. A scan tool that shows misfire counts and a visual inspection for cracked housings, heat discolouration or oil in the plug wells will quickly tell the story.

Best practice on a Lancer is to inspect coils whenever the plugs are out. If one coil fails, replacing the faulty unit is fine, if the vehicle has high kilometres and multiple intermittent misfires, a full set can save repeat labour. Always fit quality OEM-equivalent coils, keep the boots clean and dry, and lightly apply dielectric grease to the inner boot to discourage tracking. If oil is found in the wells, fix the rocker cover gasket first, or new coils may fail early.

Spark plugs and coils work as a team. Fresh iridium plugs at the correct gap reduce coil workload, improving longevity. When refitting, seat the coils squarely, route the loom correctly, and tighten fasteners to the service manual spec to avoid vibration or poor contact. If yours is a diesel Lancer, skip all of the above—no ignition coils are fitted, and any no-start or smoke issues will relate to glow plugs, fuel delivery or compression, not spark.

• Common coil symptoms: hard starting, rough idle, misfire under load, poor fuel economy, MIL on.
• Diagnostics: scan for misfire codes (e.g., P0301–P0304), swap coils cylinder-to-cylinder, inspect boots and connectors.

FAQs

How many ignition coils are on a 2010 Mitsubishi Lancer?
The petrol Lancer uses one coil per cylinder, so four coils on four-cylinder models (including Ralliart and Evo X variants). Diesel versions don’t use ignition coils at all.

Do ignition coils need routine replacement?
Not on a time basis. They’re replaced when symptoms or testing point to a fault. Keeping the spark plugs fresh and the plug wells dry helps coils last well past 150,000 km.

What are the tell-tale signs of a failing coil?
Misfire under load, rough idle, a flashing check engine light, poor fuel economy, and sometimes a sulphur-like exhaust smell. A scan tool and a simple coil swap test will usually confirm it.