Parts for your 2013 Subaru Outback-Ignition coils

2013 Subaru Outback ignition coils — what they do and when to replace them

Based on Subaru’s Factory Service Manual for MY2013 Outback (Ignition section), Subaru Global Service Information (TechInfo), and Subaru parts catalogues (FAST/Microcat), ignition coils are fitted to the petrol 2013 Subaru Outback models (2.5i FB25 and 3.6R EZ36) as coil-on-plug units. The 2.0D diesel Outback does not use ignition coils because it relies on compression ignition and glow plugs instead.

For petrol models, the ignition coils are the unsung heroes turning the car’s 12 volts into the big spark the plugs need. Each cylinder gets its own coil-on-plug unit — four on the 2.5i, six on the 3.6R — for crisp starts, smooth idle, solid power and reliable fuel economy. They sit right on top of the spark plugs, reducing energy loss and keeping timing sharp under all conditions.

There’s no fixed replacement interval for coils, but they should be checked during routine servicing, especially when spark plugs are due (typically around 100,000 km on iridium-plug petrol models, always follow the handbook). Good workshop practice is to inspect coil boots for cracking, tracking marks and oil or moisture in the plug tubes, confirm snug electrical connectors, and use a dab of dielectric grease on reassembly.

• Common signs a coil is failing: rough idle, hard starts, sluggish acceleration, increased fuel use, a flashing or solid check engine light, and misfire codes like P0301–P0306.
• Diagnostic tips: scan for codes and misfire counters, do a “swap test” by moving a suspect coil to another cylinder, and check plug condition and gap.
• Replacement advice: quality OEM or reputable aftermarket coils are worth it, replace only the faulty unit, but on high‑kilometre cars it’s reasonable to do the full bank or set. Tighten mounting bolts to factory spec and clear codes after a road test.

DIY-friendly? On the 2.5i, access is straightforward with basic tools. The 3.6R’s rear coils are tighter against the firewall, so patience (and sometimes removing intake bits) helps. Always work on a cool engine, disconnect the battery, and never tug a coil off a running engine. If the vehicle is the 2.0D diesel, ignore coil talk — it uses glow plugs and a different control strategy entirely.

Popular questions

How many ignition coils does a 2013 Subaru Outback have?
Petrol 2.5i models have four coils (one per cylinder). The 3.6R has six. The 2.0D diesel has none, because it doesn’t use spark ignition — it uses compression ignition and glow plugs.

When should the ignition coils be replaced?
There’s no set schedule. Replace coils when they cause misfires, hard starts, rough running or trigger fault codes. It’s smart to inspect them whenever plugs are changed (around 100,000 km on many petrol models) and any time misfire diagnostics point to a weak coil.

Can they be replaced at home?
Yes on the 2.5i with basic hand tools. The 3.6R is tighter for access but still doable for a careful home mechanic. Always follow the factory procedure, keep the plug tubes clean, and reconnect everything to spec.