Parts for your 2016 Subaru Impreza-Camshaft sensor

2016 Subaru Impreza Camshaft Sensor — Purpose, fitment and service tips

For the 2016 Subaru Impreza (GJ/GP) with the FB20 2.0L DOHC boxer engine, a camshaft position sensor is absolutely fitted and relevant. Technical references including the Subaru Factory Service Manual for the 2016 Impreza (Engine Diagnostics/OBD and Engine Electrical sections) and the Subaru Electronic Parts Catalogue confirm two camshaft position sensors are used — one per cylinder bank — to support dual AVCS (variable valve timing) and precise fuel and spark control. These sources also list diagnostic routines and DTCs such as P0340/P0341 (Bank 1) and P0345/P0346 (Bank 2) for camshaft position signals.

The camshaft sensor’s job is to report the exact cam angle to the ECU so timing of injection, ignition and AVCS phasing stays spot on. Working together with the crank sensor, it ensures smooth starts, clean idle, good fuel economy and low emissions. On the FB20, accurate cam feedback lets the ECU shift valve timing seamlessly across the rev range, which is why the sensor’s signal quality really matters.

It isn’t a scheduled replacement item in the service book, it’s replaced only if faulty. Telltales owners may notice include longer cranking, rough running, flat spots, higher fuel use, or the engine light with related fault codes. Because the sensor is a Hall-effect unit reading a toothed target on the cam, faults can come from the sensor itself, wiring/connectors, or timing correlation errors. Fresh, correct-spec engine oil helps AVCS operation and can reduce false correlation codes.

• Common DTCs: P0340, P0341, P0345, P0346, correlation codes like P0016–P0018 may also appear.
• Typical locations: rear of each cylinder head (left and right banks) under the bonnet, each held by a single bolt with an O-ring seal.

Replacement is a straightforward driveway job for many enthusiasts: disconnect the negative battery terminal, unplug the sensor, remove the retaining bolt, and ease the sensor out. Lightly oil the new O-ring, seat it fully, and refit the bolt snug to factory spec (refer to the Subaru Service Manual). Finally, reconnect, clear codes and road-test. Using genuine or high-quality OEM-equivalent sensors is recommended, part numbers can vary by VIN and market, so checking the EPC against the vehicle’s details is wise.

If symptoms persist after sensor replacement, inspecting the loom for damage, checking engine grounds, and verifying cam/crank timing correlation with a scan tool is the next logical step.

• Where is the camshaft sensor on a 2016 Impreza?
  The 2016 Impreza’s FB20 engine uses two camshaft position sensors, one on each cylinder head near the rear. Each sensor sits in the head with a single retaining bolt and an electrical connector, accessible from the top with basic hand tools.
• What are common symptoms of a failing camshaft sensor?
  Owners may notice extended cranking, intermittent stalling, uneven idle, reduced performance, or the check engine light. Scan tools often show codes like P0340/P0345. Sometimes wiring or connector issues can mimic a failed sensor.
• Is it safe to drive with a bad camshaft sensor?
  The car may still run but performance and reliability suffer, and it can stall. Prolonged driving is not recommended, as incorrect timing can stress components and increase fuel use. Prompt diagnosis and repair are the safest bet.