Parts for your 2014 Subaru Legacy-Ignition coils

2014 Subaru Legacy ignition coils

Technical sources confirm the 2014 Subaru Legacy (sold as Liberty in Australia) absolutely uses ignition coils. The Subaru Factory Service Manual for the 2014 Legacy/Outback (engine section, ignition control) and Subaru’s global parts catalogue both specify individual coil-on-plug ignition coils for the FB25 2.5‑litre four and EZ36 3.6‑litre six. That means there’s one coil sitting on top of each spark plug: four on the 2.5, six on the 3.6.

What do they do? Each ignition coil steps up 12 volts from the battery to tens of thousands of volts, creating the spark that lights the air–fuel mix. Coil-on-plug keeps the spark strong and timing accurate, helping the Legacy run smoothly and efficiently.

They’re not a scheduled replacement item, but they do wear with heat, vibration, and age. Typical signs a coil’s on the way out include:

• Rough idle, hesitation, or a flat spot under load
• Engine light on with misfire codes (P0301–P0306) or coil circuit codes (P0351–P0356)
• Higher fuel use and a whiff of raw fuel from the exhaust

Good servicing habits help coils last:

• Inspect coils and boots whenever spark plugs are replaced (check your logbook interval, commonly around 100,000 km)
• Keep moisture and oil out of the plug tubes, fix any rocker cover/tube seal leaks
• Use quality plugs gapped to spec, a bad plug stresses a good coil
• Apply a light smear of dielectric grease inside the boots if recommended by the manual

Replacement on the FB25/EZ36 is straightforward but space can be tight on the lower cylinders. Usual approach under the bonnet:

1. Disconnect the negative battery terminal
2. Remove the airbox or battery for access where needed
3. Unplug the coil connector, undo the hold‑down bolt, twist and pull the coil straight out
4. Check for oil or corrosion in the plug well, address leaks before refitting
5. Install the new coil, seat the boot fully on the plug, tighten the bolt to factory spec, reconnect the plug
6. Clear any stored codes and road‑test

It’s fine to replace a single failed coil, though if multiple coils are original and kilometres are high, doing them in pairs or a full set can save repeat visits. Driving with a bad coil risks catalytic converter damage, so it’s best sorted promptly. Any capable local workshop in Australia or New Zealand can handle the job.

Popular questions

Does a 2014 Subaru Legacy/Liberty use individual coils or a single coil pack?
It uses individual coil-on-plug units: four on the 2.5‑litre and six on the 3.6‑litre. This layout improves spark energy and reduces high‑tension wiring compared with an old central coil pack.

How often should the ignition coils be replaced?
There’s no fixed interval. Inspect them whenever spark plugs are serviced (about every 100,000 km, per the vehicle’s maintenance schedule). Replace coils only if they test faulty or show symptoms.

Is it safe to drive with a failing coil?
It may still run, but driving on a misfire can damage the catalytic converters and O2 sensors. If a coil is failing, reduce driving and book a repair sooner rather than later.