Parts for your 2018 Subaru Legacy-Camshaft sensor

2018 Subaru Legacy camshaft sensor — what it does and how to look after it

Based on technical sources, the 2018 Subaru Legacy is fitted with camshaft position sensors. The Subaru Service Manual for the 2018 Legacy/Outback (Engine Diagnostics section), the Subaru Technical Information System (STIS), and OEM parts catalogues list camshaft position sensors as integral components for both the 2.5‑litre FB25 and 3.6‑litre EZ36 engines. These documents also detail related diagnostic trouble codes (for example P0340/P0345) and test procedures, confirming the sensor’s role in engine management.

The camshaft sensor tells the engine control unit exactly where the camshafts are in their rotation. That signal lets the ECU time fuel injection and ignition precisely and manage Subaru’s AVCS variable valve timing. If the sensor drops out or reads poorly, starting takes longer, idle can get rough, fuel economy suffers, and the car may fall into limp mode while lighting the check engine lamp.

On the 2018 Legacy, the 2.5L FB25 typically uses two camshaft sensors (one per bank), while the 3.6L EZ36 uses four (intake and exhaust per bank). Location is at the front or upper edge of each cylinder head under the bonnet, with easy visual access once covers are off.

It’s not a scheduled replacement item, so there’s no set kilometre interval. During servicing, it’s smart to give the connectors and harness a quick inspection, keep the area free of oil weeps, and make sure the sensor mounting and O‑ring aren’t seeping. Use the ECU’s live data if available to check cam/crank synchronisation, especially if there are any drivability niggles.

• Signs it’s on the way out: hard starting after a heat soak, intermittent stalling, flat spots on acceleration, poorer fuel use, and codes like P0340, P0341, P0345, or cam/crank correlation codes (P0016–P0019).
• Service tips: verify power, ground, and signal at the plug, inspect for rubbed-through wiring near the timing cover, replace the O‑ring with the sensor, and avoid contaminating the sensor face with sealant or oil.

Replacement is usually straightforward: disconnect the battery, unplug the connector, remove the retaining bolt, twist the sensor gently to free the O‑ring, swap in a quality OEM‑spec unit, and torque the bolt to the figure in the Subaru manual. Clear the codes, start the engine, and let it idle, then take a short drive so the ECU can relearn. If a new sensor doesn’t sort it, look at timing chain stretch, AVCS oil control solenoids, oil quality, or wiring faults before throwing more parts at it.

Does the 2018 Subaru Legacy have a camshaft sensor, and how many are there?

Yes. Technical documentation confirms the 2018 Legacy uses camshaft position sensors. The 2.5L FB25 generally has two (one per bank), while the 3.6L EZ36 has four (one per cam). Exact fitment can vary by VIN.

What faults or codes point to a bad camshaft sensor on a 2018 Legacy?

Common signs include rough idle, long crank when hot, stalling, and the check engine light. Typical OBD‑II codes are P0340/P0341 (Bank 1) and P0345/P0346 (Bank 2). Cam/crank correlation codes like P0016–P0019 can also appear if timing or the sensor signal is off. Always check wiring and oil condition before replacing parts.

Is it safe to drive with a failing camshaft sensor?

It’ll often run, but performance can be down, fuel use up, and stalling is possible — not ideal in Aussie or Kiwi traffic. It’s best to diagnose and repair promptly to avoid being stranded and to minimise knock-on issues with the catalytic converter or AVCS system.