Parts for your 2009 Subaru Impreza-Crank angle sensor

2009 Subaru Impreza crank-angle-sensor (crankshaft position sensor)

Based on technical references including the Subaru Factory Service Manual for the GE/GH/GR Impreza (2008–2011) and Subaru’s FAST electronic parts catalogue, the 2009 Subaru Impreza is fitted with a crankshaft position sensor—often called a crank-angle-sensor. The FSM details diagnostics for DTC P0335/P0338 and shows the sensor mounted at the rear of the engine near the bellhousing, confirming its use across EJ25 engines (EJ253/EJ255/EJ257). Independent repair manuals covering 2002–2011 Impreza models also document the same sensor and test procedures, so it’s absolutely relevant on this model year.

On the 2009 Impreza, the crank-angle-sensor feeds the ECU with precise crank speed and position data. The ECU uses that signal to time spark and fuel injection, coordinate with the cam sensors for AVCS (where fitted), and monitor for misfire. If the signal drops out, the car can stumble, cut out, or refuse to start—no guesswork needed.

It’s not a routine replacement item, but heat, vibration and age can take their toll. Telltale signs that the 2009 Subaru Impreza crank-angle-sensor needs attention include:

• Hard starting or a complete no-start when hot or at random
• Intermittent stalling, rough running, or sudden loss of power
• Check Engine Light with codes like P0335/P0338
• Tach needle dropping to zero while the engine is still spinning

Basic service advice: keep connectors clean and dry, and don’t pressure-wash the area. If oil leaks are present at the back of the engine, sort them—oil contamination can attack the connector seals over time. The sensor isn’t adjustable and there’s no gap to set on EJ engines.

Replacement is straightforward for a competent DIYer or any workshop:

• Disconnect the battery negative.
• Locate the sensor at the rear/top of the engine block near the bellhousing and pitch-stop mount.
• Unplug the connector, remove the single retaining bolt, and pull the sensor straight out.
• Lightly oil the new O-ring, install the new sensor flush, and torque the bolt to the factory spec in the Subaru FSM.
• Reconnect, clear codes, and road-test. No programming is required.

Use a quality OEM or reputable aftermarket sensor. Also check the harness for chafing around the intake and firewall—repair any damaged loom to prevent future dramas. Done right, the new crank-angle-sensor will restore crisp starts and smooth running for heaps of kilometres.

Where is the crank-angle-sensor on a 2009 Subaru Impreza?

It’s mounted at the back of the engine block near the bellhousing, close to the pitch-stop mount. On naturally aspirated models it’s usually reachable from the top, on turbo models, access can be tighter but still manageable with basic tools.

Do I need to program the new sensor after replacement?

No programming is required. Fit the new sensor, torque the bolt to spec, clear any fault codes, and the ECU will read it straight away. A short drive cycle helps the ECU complete its checks.

Is it safe to keep driving with a failing crank-angle-sensor?

Not recommended. Intermittent failure can cause stalling or a no-start at the worst time. If symptoms or codes point to the sensor, sort it promptly to avoid getting stranded.