Parts for your 2003 Subaru Impreza-Crank angle sensor

2003 Subaru Impreza crank-angle-sensor (crankshaft position sensor)

Yes, the 2003 Subaru Impreza is fitted with a crank-angle sensor, more commonly called the crankshaft position (CKP) sensor. This is confirmed by multiple technical sources:

• Subaru Factory Service Manual (2003MY Impreza): Engine Diagnostics sections list the Crankshaft Position Sensor and DTCs P0335/P0336, plus test procedures.
• Subaru parts catalogue (EJ20/EJ25 engines): CKP sensor is listed for 2003 Impreza models, common genuine part numbers include 22056AA061 and 22056AA063 (varies by VIN/market).
• Haynes Repair Manual for Subaru Impreza 2002–2011: Covers CKP sensor operation, testing and replacement.

On the 2003 Impreza, the crank-angle sensor sits at the front of the engine, typically behind the alternator, reading a toothed reluctor on the crank sprocket. Its job is to tell the ECU exactly where the crank is in its rotation and how fast it’s spinning. That real‑time signal lets the ECU time spark and fuel precisely and sync with the cam sensor. If the sensor drops out, the engine can be hard to start, run rough, stall, or not start at all. The check engine light may log codes like P0335 or P0336.

There’s no scheduled maintenance for the CKP sensor, but a quick look during services pays off. Under the bonnet, check the connector and loom near the alternator for rubbing or heat damage, and keep the plug clean and dry. Avoid pressure‑washing the area. If you’re doing a timing belt, it’s a neat time to inspect the sensor tip and O‑ring.

Replacement is straightforward for most DIYers with basic tools. Disconnect the battery negative, remove the intake snorkel if it’s in the way, unplug the sensor, and undo the single retaining bolt (10 mm head). Gently twist the sensor to free the O‑ring. Lightly oil a new O‑ring, seat the new sensor fully, and tighten the bolt to the factory torque spec from the Subaru manual. Reconnect, clear any codes, and let the ECU relearn idle with a short drive cycle. Use a quality genuine or OEM‑equivalent sensor, cheap copies can give flaky signals and hot‑soak issues.

Common symptoms of a failing CKP on these EJ engines include intermittent no‑start when hot, sudden stalling at idle or when coming to a stop, erratic tacho behaviour, and longer crank time. If those crop up, don’t keep driving and hope for the best—sort it early to avoid getting stranded.

Popular questions

Where is the crank-angle sensor on a 2003 Subaru Impreza?

It’s mounted at the front of the engine, usually just behind the alternator and above the crank pulley, reading the reluctor on the crank timing sprocket. On most EJ engines you can reach it from the top once the intake snorkel is out of the way.

Can you drive with a bad crank-angle sensor?

You might get intermittent running, but it can cut out without warning and then refuse to restart—especially when hot. It’s not worth the risk. If the 2003 Impreza shows P0335/P0336 or matching symptoms, plan a repair straight away.

Do the crank and cam sensors need replacing together?

Not necessarily. Replace the faulty one after proper diagnosis. That said, on higher‑kilometre cars, if one has failed and both are the same age, some owners choose to replace the other as preventive maintenance, particularly before long trips.