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Parts for your 2020 Subaru Legacy-Camshaft sensor
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2020 Subaru Legacy camshaft sensor: what it does and how to keep it sweet
Based on technical sources, the 2020 Subaru Legacy absolutely uses a camshaft sensor (often two, one per cylinder bank). The Subaru Factory Service Manual for the 2020 Legacy/Outback platform documents diagnostic routines and DTCs such as P0340/P0345 (Camshaft Position Sensor “A”/“B” circuit), and Subaru’s OEM parts catalog lists dedicated camshaft position sensors for the 2.5‑litre FB25 and 2.4‑litre turbo FA24 engines. Subaru’s AVCS (Active Valve Control System) and sequential fuel injection strategies rely on live cam position data, confirming the sensor is fitted and essential.
On a 2020 Legacy, the camshaft sensor tells the ECU exactly where each cam is in its rotation. That lets the ECU fire injectors and spark with precision, trim timing at idle, and drive the AVCS for grunt and efficiency. When the sensor’s healthy, cold starts are crisp, fuel economy stays tidy, and the engine feels smooth under load. When it’s crook, the car may crank longer, stumble, throw a CEL, log cam/crank correlation faults, and drop into a limp mode.
There’s no set service interval for the camshaft sensor, but a bit of preventative care goes a long way:
- Keep connectors clean and latched, road grime and moisture can cause intermittent signals.
- Fix any oil leaks under the bonnet—oil ingress at the plug can upset the signal.
- If chasing hesitation or hard starts, scan for DTCs and check live cam angle, don’t just throw parts.
Replacement is straightforward for most home tinkerers with a basic spanner set and a scan tool:
- Confirm the fault with proper diagnostics (waveform or live data is best).
- Disconnect the battery, unplug the sensor, and remove the retaining bolt.
- Inspect the O‑ring, replace it if it’s flattened or torn. Lightly oil the new O‑ring.
- Install the new sensor to the correct torque, reconnect, and clear codes. Perform an idle relearn if noted in the service manual.
Use a genuine or high‑quality aftermarket sensor that matches the engine code. After fitting, a quick road test with live data should show stable cam angle tracking and no fresh codes. Look after the sensor and wiring, and the Legacy’s ECU will keep timing bang‑on for heaps of kilometres without drama.
Does the 2020 Subaru Legacy have more than one camshaft sensor?
Most 2020 Legacy engines use a sensor on each cylinder bank to track cam position for AVCS and sequential injection. Exact count and placement depend on engine variant, but the factory service information lists multiple cam-related inputs.
What symptoms point to a failing camshaft sensor on a 2020 Legacy?
Common signs include long crank, rough idle, misfires at low rpm, poor fuel economy, and a check engine light with cam/crank correlation codes like P0340 or P0345. Always verify with a scan tool before replacing parts.
Is a camshaft sensor replacement a DIY job?
Often, yes. With basic tools and care around connectors and O‑rings, it’s a tidy job. If faults persist after replacement, dig deeper into wiring, timing alignment, or AVCS control rather than swapping more sensors.
