Parts for your 2007 Subaru Impreza-Crank angle sensor

2007 Subaru Impreza crank angle sensor (crankshaft position sensor)

Based on the Subaru Factory Service Manual for the 2007MY Impreza/WRX/STI (engine management section), as well as common repair data from Haynes and Autodata, the 2007 Subaru Impreza is fitted with a crank angle sensor, identified in the manual as the crankshaft position sensor (CKP). It’s a critical input for the ECU and absolutely relevant to this model.

This sensor’s job is straightforward but vital: it tracks crankshaft speed and exact position so the ECU knows when to fire the spark and deliver fuel. On the 2007 Impreza’s EJ-series engines, the CKP works in tandem with the cam sensors to keep ignition timing and injection perfectly in sync. If the signal drops out, the engine can stall, refuse to start, or run roughly. Typical fault codes you’ll see are P0335–P0339.

While the crank angle sensor isn’t a scheduled service item, it’s smart to give it a bit of attention during routine servicing. Under the bonnet, check the sensor connector and harness for heat hardening, chafing, or oil contamination. Oil leaks that track down the front of the engine or along the loom can foul the plug, cleaning and fixing the leak early helps avoid false triggers. Keeping the connector seated firmly and the loom clipped away from pulleys or the exhaust goes a long way.

Replacement is usually a simple driveway job for a confident home mechanic. Disconnect the battery, unplug the sensor, remove the single retaining bolt, and ease the sensor out—there’s an O-ring, so a gentle twist helps. Lightly oil the new O-ring, seat the new sensor flush, and tighten the bolt to factory spec. Reconnect, clear codes, and check for a clean crank signal. Use an OE or high-quality equivalent part, cheap sensors can give weak or noisy signals that cause intermittent no-starts. No special “learning” procedure is typically required, the ECU reads the signal on the next start.

If the car shows hard starting when hot, random stalling at idle, or a wildly flickering tacho, it’s worth scanning for CKP-related codes before chasing fuel issues. A solid diagnosis—verifying power, ground, and signal at the sensor—will save guesswork and parts.

• Common symptoms: long crank/no start, sudden stall, misfire, rough idle, CEL with P0335–P0339.
• Service tip: inspect wiring and connector every 20,000–30,000 kilometres, especially after oil leaks or engine work.

Popular questions about the 2007 Subaru Impreza crank angle sensor

Where is the crank angle sensor on a 2007 Subaru Impreza?
It’s mounted on the engine block and reads a toothed wheel on the crankshaft. Access is from under the bonnet, it’s secured with a single small bolt and has a two-pin or three-pin connector depending on engine variant. Exact placement can vary slightly between the EJ253 (2.5i) and EJ255/257 (WRX/STI), but it’s always positioned to monitor crank rotation directly.

What are the signs the crank angle sensor is failing?
Owners commonly report long cranking, intermittent no-start (often when hot), random stalling at lights, and a check engine light. Scan tools typically show codes P0335–P0339. The tachometer may flicker or drop to zero briefly when the signal cuts out. These symptoms can mimic fuel issues, so scan first before replacing parts.

Should it be replaced as preventive maintenance?
Not usually. The sensor isn’t a wear item and is replaced on condition. During regular servicing, inspect the connector and loom for heat damage or oil intrusion and tidy any loose clips. If replacement is needed, choose an OE or reputable brand sensor and ensure the mounting face is clean so the air gap is correct.