Parts for your 2015 Subaru Impreza-Camshaft sensor

2015 Subaru Impreza Camshaft Sensor — Purpose, Fitment and Service Advice

Based on technical references, the 2015 Subaru Impreza is equipped with camshaft position sensor(s). The Subaru Factory Service Manual for the 2015 Impreza (Engine diagnostics) lists fault codes and test procedures for the camshaft position sensor circuit (e.g., DTC P0340/P0341), confirming it’s an active input to the ECU. Subaru’s official parts catalogues for the FB20 2.0‑litre engine also list camshaft position sensor assemblies for this model year, with part numbers varying by VIN and market. That means the camshaft sensor is relevant and used on this vehicle.

On the 2015 Impreza’s FB‑series DOHC boxer engine with Active Valve Control System (AVCS), the camshaft sensor tells the engine computer exactly where the cam(s) are in relation to the crank. The ECU uses that live signal to time fuel injection and spark, and to control valve timing for better torque, smooth idle and lower emissions. If the sensor goes out of whack, the car can be hard to start, run rough, feel gutless, or throw a check‑engine light.

There’s no scheduled replacement interval for the camshaft sensor, it’s generally a fit‑and‑forget part. During routine servicing, it’s smart to visually check the sensor connector and harness for oil weep, corrosion or chafing, and make sure the engine oil is the correct grade and changed on time. Clean, correctly‑viscous oil helps the AVCS operate smoothly, which in turn keeps cam/crank correlation healthy.

If replacement is needed, most workshops will confirm the fault by scanning for codes such as P0340/P0341 and checking live data for cam/crank sync. They’ll also rule out wiring faults before swapping the sensor. Replacement is typically straightforward: disconnect the battery, unplug the sensor, remove its retaining fastener, swap the O‑ring if fitted, install the new unit, and tighten to the workshop manual’s torque spec. No special relearn is usually required, the ECU will pick up the new signal after a short drive cycle. Using a quality OEM‑equivalent sensor avoids intermittent gremlins.

• Common symptoms: hard starting, rough idle, misfire feel, poor fuel economy, limp mode, check‑engine light.
• Pro tips: inspect wiring before replacing, avoid oil contamination at the connector, verify with scan data, not just a code.
• Fitment note: many FB20 variants use two cam sensors (one per bank), always confirm by VIN.

Popular questions about the 2015 Subaru Impreza camshaft sensor

Does the 2015 Impreza have one or two camshaft sensors?
Most FB20 engines in the 2015 Impreza use two camshaft sensors (one on each cylinder bank). The exact setup and part numbering can vary with trim and market, so it’s best to check by VIN or sight under the bonnet.

What are the signs a camshaft sensor is failing on this model?
Owners often notice longer cranking, stumbling idle, flat spots, reduced fuel economy, and a check‑engine light. Scan tools may show DTCs P0340/P0341 or cam/crank correlation errors. Similar symptoms can also come from wiring issues, so diagnosis matters.

Can a camshaft sensor be cleaned instead of replaced?
They’re solid‑state devices, cleaning rarely brings a lasting fix. If contamination is present, address oil leaks and connector condition, but if the sensor’s signal is erratic or out of spec per the service manual tests, replacement is the reliable cure.