Parts for your 2009 Mitsubishi Lancer-Ignition coils

2009 Mitsubishi Lancer ignition coils — what they do and how to look after them

Ignition coils are fitted to the 2009 Mitsubishi Lancer petrol range. Technical references that confirm this include the Mitsubishi Motors CJ Lancer Service Manual (2008–2010) detailing a coil-on-plug system for the 4B11/4B12 and 4B11T engines, the Haynes Repair Manual for Lancer (2007–2017), and the Mitsubishi ASA electronic parts catalogue listing individual ignition coils for these engines. Only the rare 2.0 DI-D diesel (compression-ignition) variant doesn’t use coils, as it doesn’t require spark plugs.

On the 2009 petrol Lancer, each cylinder has its own coil mounted directly on the spark plug (coil-on-plug). That layout shortens the path for high voltage, delivers a stronger, cleaner spark, and cuts out old-school leads. The result is smoother starting, better fuel economy, and lower emissions when everything’s healthy.

Coils aren’t a routine replacement item, but they do live a hot, hard life under the bonnet. A good time to inspect them is when the spark plugs are changed—typically around 90,000–100,000 km for iridium plugs, per common service guidance. Look for cracking on the coil body, swollen or oil-soaked boots, green or white corrosion on terminals, or arcing marks. If the Lancer shows a rough idle, sluggish performance, higher fuel use, or logs misfire codes (often P0300–P0304 or coil primary/secondary faults like P0351–P0354), a failing coil is a prime suspect.

Replacement is straightforward for competent DIYers: remove the engine cover, unplug the coil connector, undo the small retaining bolt, then twist and lift the coil from the plug well. Seat the new unit firmly, refit the bolt (don’t overtighten), reconnect, and repeat for any others. A tiny smear of dielectric grease on the inside of the boot can help future removal and seal out moisture—keep it off the electrical pins.

Owners can replace just the failed coil, but on higher-kilometre cars it’s sensible to budget for any weak siblings over time. Use quality OEM-spec coils, cheapies can work, but inconsistent output often means the misfire gremlin returns. Keeping water out of the plug wells (after washing the engine bay, for example) and fixing any rocker cover gasket weeps will dramatically extend coil life.

• Common symptoms: misfire under load, hard starts, rough idle, flashing check engine light
• Best practice: inspect coils whenever plugs are serviced, address oil leaks promptly
• Note: Ralliart and Evo X models also use four coil-on-plug units—specs and part numbers can differ, so match by VIN

Popular questions

How often should the ignition coils be replaced on a 2009 Lancer?

There’s no fixed interval. Coils are replaced when faulty or showing clear degradation. A practical approach is to inspect them during spark plug changes around 90,000–100,000 km and test if misfire symptoms appear. Many last well past 150,000 km in Aussie and Kiwi conditions if kept dry and oil-free.

Can driving with a bad coil damage the catalytic converter?

Yes. A persistent misfire can push unburnt fuel into the exhaust, overheating and contaminating the cat. If the check engine light is flashing or the engine is bucking, sort the coil issue promptly to protect the catalyst and avoid extra fuel costs.

Do Ralliart and Evo X coils interchange with the standard 2.0 petrol Lancer?

They’re all coil-on-plug, but part numbers and calibration can differ between the naturally aspirated 4B11 and the turbo 4B11T. To avoid fitment or performance issues, match coils to the exact model and VIN rather than assuming interchangeability.