Parts for your 2002 Mitsubishi Lancer-Camshaft sensor

2002 Mitsubishi Lancer camshaft sensor — what it does and when to replace it

Based on the 2002 Mitsubishi Lancer CG/CH factory service manual (Engine Electrical/MFI sections) and the Mitsubishi ASA parts catalogue for CG/CH/CS series, the 2002 Lancer is fitted with a camshaft position sensor. Technical data from common service platforms (e.g., Autodata and OE supplier catalogues) also lists a dedicated CMP sensor on the 4G9-series engines used in this model year. So yes—this Lancer uses a camshaft sensor, and it’s an essential part of the engine management system.

The camshaft sensor tells the ECU exactly where the cam is in its rotation. That timing reference lets the ECU run sequential fuel injection and correctly fire the ignition. If it goes out of whack, the ECU can’t sync fuel and spark perfectly, leading to hard starting, rough running, or a sudden stall at the lights. On this Lancer, the sensor sits on the timing-belt end of the cylinder head, reading a trigger on the cam.

It’s not a scheduled service item like oil or a timing belt, but it pays to keep an eye on it during regular servicing. A healthy sensor and clean wiring keep the ECU happy and the fuel economy tidy. Many “sensor failures” are actually wiring or connector issues, or even a timing-belt correlation fault. If the belt is stretched or out a tooth, you can see cam/crank codes despite the sensor being fine—so always check timing-belt condition and alignment, especially past the typical 100,000 km/5–7 year interval.

• Common symptoms: Check Engine light (often P0340/P0341), long crank, misfire, poor idle, limp mode, or stalling.
• Quick checks: inspect the harness under the bonnet for brittle insulation, oil contamination around the sensor, and a loose or corroded connector.

When replacement is needed, use quality OE-spec parts. The job is straightforward with basic tools: disconnect the battery, remove the engine cover/air ducting for access, unplug the sensor, and undo its small retaining bolt. Lightly oil the O-ring on the new sensor, seat it squarely, and tighten the fastener to the workshop manual’s light torque spec (don’t overdo it with a big spanner). Plug it in, clear codes with a scan tool, and let the ECU relearn at idle. If the light returns, revisit wiring integrity and confirm cam/crank correlation to rule out timing-belt issues.

Treat the connector with dielectric grease, keep oil leaks sorted, and this little sensor will quietly get on with the job for years.

FAQs

Where is the camshaft sensor on a 2002 Mitsubishi Lancer?

It’s mounted on the timing-belt end of the cylinder head, near the top front corner of the engine. Under the bonnet, look toward the cam gear area, you’ll see a small sensor with a single electrical plug held by a small bolt.

What are the signs the camshaft sensor is failing on a CG/CH Lancer?

Typical signs include long cranking, rough idle, random stalling, and the Check Engine light with codes like P0340/P0341. If the timing belt has jumped a tooth, you can get similar symptoms—so verify belt timing before condemning the sensor.

Can you keep driving with a dodgy camshaft sensor?

It might run, but it can be hard to start, drop into limp mode, or stall unexpectedly. Best to sort it promptly to avoid getting stuck and to protect the engine from poor running conditions.