Parts for your 2007 Mitsubishi Lancer-Ignition leads

2007 Mitsubishi Lancer ignition leads: what they are, and whether your Lancer has them

For Australian and New Zealand 2007 Lancers, whether ignition leads are relevant depends on the exact model. Technical publications confirm this split: the CH-series Lancer (built up to around mid‑2007, typically with the 4G94 2.0) uses ignition leads/HT leads, as shown in the Mitsubishi CH Lancer Workshop Manual (Ignition System), and supported by NGK and Bosch Oceania catalogues that list lead sets for CH. The later CJ-series Lancer (released late 2007 with the 4B11 MIVEC) runs coil‑on‑plug ignition with no HT leads, as detailed in the Mitsubishi CJ Lancer Service Manual (4B11 Ignition section) and common service databases such as Autodata. So, if it’s a CH, ignition leads apply, if it’s a late‑2007 CJ, they’re not used.

When fitted (CH-series), the ignition leads play a simple but crucial role: they carry high voltage from the coils to the spark plugs cleanly and reliably, so the engine fires crisply under all loads. Quality leads provide strong insulation against heat and oil, proper suppression to keep electrical noise out of sensors and the radio, and consistent resistance so each cylinder gets a healthy spark. As they age, heat cycling, engine bay oil mist, and handling can cause cracks, hardening, or internal resistance changes. The result can be misfires, rough idle, higher fuel use, and that tell‑tale check‑engine light.

Good servicing practice on a 2007 CH Lancer is to inspect the leads at every major service and consider replacement around 60,000–100,000 kilometres or 5 years, sooner if there are symptoms. Look for perished boots, white tracking marks, loose fit on coils or plugs, or any rubbing where a lead touches metal. If replacing, do them as a set, one lead at a time to preserve firing order, and route them through the original separators so they don’t rest on hot or sharp spots. A light smear of dielectric grease inside the boots helps future removal and keeps moisture out. Pair fresh leads with the correct spark plugs gapped to spec, and check the coil connectors and mounting while in there. If a misfire code is stored (often P0300–P0304), leads are a common fix on CH, but always rule out tired plugs or a weak coil too.

For owners of the late‑2007 CJ, there are no ignition leads by design. Its coil‑on‑plug setup mounts a coil directly on each spark plug for tighter spark control and fewer high‑voltage losses, which is why parts catalogues won’t list HT leads for CJ. If there’s a misfire on a CJ, attention shifts to the plugs, the individual coils, or wiring/connectors rather than leads.

• CH (up to mid‑2007): ignition leads used and serviceable items.
• CJ (late‑2007 onward): no ignition leads, coil‑on‑plug only.

Popular questions about 2007 Mitsubishi Lancer ignition leads

Does a 2007 Lancer have ignition leads?
It depends on the series. CH models (early 2007) do use ignition leads. Late‑2007 CJ models don’t, as they have coil‑on‑plug. Check the build plate or look under the cover: visible HT leads point to a CH, a pencil‑style coil on each plug points to a CJ.

How often should the CH Lancer’s ignition leads be replaced?
Plan on 60,000–100,000 kilometres or about 5 years, and sooner if there are misfires, rough running, or visible damage. Heat, oil vapour and age are the main culprits. Quality replacements from reputable brands help the engine stay smooth and efficient.

Can a home mechanic replace CH ignition leads?
Yes, it’s a straightforward DIY for many. Work one lead at a time, match lengths, keep the original routing, and ensure each boot clicks home on the plug and coil. If unsure of firing order or cylinder numbering, refer to the factory manual to avoid cross‑firing.