Parts for your 2005 Subaru Forester-Camshaft sensor

2005 Subaru Forester Camshaft Sensor — What It Does and When to Replace It

The 2005 Subaru Forester is fitted with a camshaft position sensor. This applies to both the 2.5-litre non‑turbo (EJ253 SOHC) and turbo XT (EJ255 DOHC with AVCS) models. Subaru’s factory service manual for the 2005MY Forester (SG) details the camshaft position sensor in the Engine Diagnostics section, and the Subaru Electronic Parts Catalogue lists the “Camshaft Position Sensor” for these engines (with the AVCS turbo models using a sensor on each intake cam). These references are consistent with independent repair data such as Autodata and Haynes manuals for 2003–2008 Forester models.

On this Forester, the camshaft sensor tells the ECU exactly where the camshaft(s) sit relative to the crank. That timing info is crucial for clean starts, accurate fuel injection, stable idle, and on turbo AVCS engines, proper cam phasing. If the sensor signal goes missing or flaky, the ECU can struggle to sync, which can mean long cranks, misfires, rough running, or a check engine light (often codes like P0340/P0345).

There’s no scheduled replacement interval for the cam sensor, it’s a solid‑state part that’s generally replaced on condition. As part of routine servicing, it’s smart to give the harness and connector a once‑over: check for oil wicking, brittle wiring, or green corrosion under the plug. A quick clean of the connector with proper electrical contact cleaner can head off intermittent faults.

Replacement is straightforward under the bonnet with basic hand tools. On the SOHC non‑turbo, there’s a single sensor on the left‑hand cylinder head. On AVCS turbo models, there’s one on each intake cam. Disconnect the battery negative, unplug the sensor, remove the retaining bolt, and ease the sensor out. Lightly oil the O‑ring on the new unit, seat it squarely, and snug the bolt to factory spec—don’t overdo it. Clear any codes and confirm live data and timing sync with a scan tool. If a fresh sensor doesn’t fix a no‑start or rough idle, check the crank sensor, cam trigger pattern (timing belt alignment), power/earth feeds, and ECU grounds.

• Common symptoms: hard starting, stalling at idle, sluggish throttle, poor fuel economy, and the MIL on.
• Good practice: inspect every 20–30,000 kilometres when you’re in there for filters or plugs, especially if there are oil leaks above the sensor.
• Parts note: non‑turbo typically uses one sensor, turbo AVCS models use two. Verify by VIN in the parts catalogue.

Popular questions

Where is the camshaft sensor on a 2005 Subaru Forester?
On the non‑turbo EJ253, it’s mounted on the left‑hand cylinder head near the rear of the cam gear. On turbo EJ255 AVCS models, there’s a sensor on each intake cam—one on each bank—accessible from the top with the engine covers removed.

What are the symptoms of a failing camshaft sensor on a 2005 Forester?
Expect long crank times, misfires, stumbling idle, sudden stalling, poor fuel use, and a check engine light. Diagnostic trouble codes commonly include P0340/P0345. Live data on a scan tool may show loss of cam sync during cranking or warm idle.

Do non‑turbo and turbo 2005 Foresters use the same camshaft sensor?
They’re not always the same. The non‑turbo typically uses a single cam sensor part, while the turbo AVCS models use sensors specific to the variable valve timing setup and require one per intake cam. Always cross‑check by VIN in the Subaru parts catalogue.

Technical sources referenced: Subaru Factory Service Manual, 2005MY Forester (SG) — Engine Diagnostics: Camshaft Position Sensor (H4SO/H4DO/AVCS), Subaru Electronic Parts Catalogue (2005 Forester) — Sensor, Camshaft Position listings, Autodata and Haynes Repair Manuals for 2003–2008 Forester.