Parts for your 2018 Subaru Exiga-Camshaft sensor

2018 Subaru Exiga camshaft sensor — what it does and how to look after it

Yes, the 2018 Subaru Exiga (sold in its later years as the Exiga Crossover 7) does use camshaft position sensors. This is confirmed in Subaru factory service information for the FB-series 2.5‑litre DOHC engine (which details camshaft position sensing for AVCS/variable valve timing) and in Subaru’s FAST electronic parts catalogue for the 2018 Exiga, which lists camshaft position sensors for this model. Earlier Exiga variants with EJ engines also used camshaft sensors as part of Subaru’s AVCS strategy.

On this Exiga, the camshaft sensor’s job is to tell the engine control module exactly where each cam is in its rotation, so the ECU can sync fuel injection and spark with the crankshaft and, crucially, command AVCS to advance or retard the cams. That’s how it achieves smooth cold starts, better torque through the rev range, solid fuel economy on a cruise, and cleaner emissions. If these sensors go out of whack, timing control goes with it — cue rough idle, sluggish response, and the odd stall under the bonnet when it’s least convenient.

There’s no set replacement interval for a camshaft sensor on the 2018 Exiga, it’s a “replace on fault” item. As part of regular servicing, a tech will usually check for stored fault codes (think P0340–P0349 range), inspect the sensor connectors for oil intrusion or moisture, and make sure the engine loom isn’t rubbing through near the cam covers. Keeping the area clean and using the correct engine oil spec helps the AVCS system behave and reduces false faults.

Replacement is generally straightforward for a competent DIYer or workshop. The FB25 in the Exiga uses two camshaft position sensors (one per cylinder head). Access is from up top after removing the engine cover and intake ducting, the sensors mount to the heads near the cam covers. The drill is: disconnect the battery, unplug the connector, remove the retaining bolt, swap the sensor, reconnect, clear codes, and road test to confirm AVCS operation. Use quality OEM-equivalent parts — cheapies can cause intermittent faults that’ll have the dash lit up like a Christmas tree. If symptoms persist after replacement, it’s worth checking the crank sensor and timing correlation, as the ECU needs clean signals from both to play nicely.

• Common signs: hard starting, uneven idle, flat spots, poor fuel economy, check-engine light, limp-mode behaviour.
• Good practice: inspect connectors and wiring at every service, especially after heavy rain or off‑road use.

FAQs

Where is the camshaft sensor on a 2018 Subaru Exiga?
On FB25-equipped Exiga models, each sensor is mounted on the cylinder heads near the cam covers, accessible from the top once the engine cover and intake ducting are off. They’re held by a single fastener with a simple plug-in connector.

Does the camshaft sensor need regular replacement?
No. There’s no scheduled interval — it’s replaced when faulty. During routine servicing, a quick scan for codes and a visual check of the connectors and loom is all that’s typically required.

Can a failing camshaft sensor cause stalling or poor fuel economy?
It can. If the ECU loses accurate cam position data, AVCS timing control suffers. That can lead to rough idle, stalls, hesitant acceleration and a noticeable hit to fuel economy, often with a check‑engine light.