Parts for your 2007 Subaru Forester-Ignition coils

2007 Subaru Forester ignition coils — what they do and when to replace them

Yes, the 2007 Subaru Forester uses ignition coils. Technical references including the Subaru Service Manual for MY2007 Forester (SG, Ignition System section), Subaru FAST parts catalogues, and NGK/DENSO application guides identify ignition coils across all 2007 Forester trims. Non‑turbo EJ253 models use a single four‑tower “coil pack” feeding high‑tension leads to the plugs, while turbocharged EJ255 (XT) models use four individual coil‑on‑plug units mounted directly on each spark plug.

On a 2007 Forester, the ignition coil’s job is to take the battery’s 12 volts and step it up to the serious voltage needed to jump the spark plug gap. That reliable spark is what lights the fuel–air mix, keeps the flat‑four running smoothly, and helps fuel economy stay on song. Whether it’s the single coil pack on an EJ253 or four individual COP units on an EJ255, healthy coils are vital for smooth starts, steady idle, and decent pull under load.

There’s no fixed replacement interval for coils, but they should be inspected during routine servicing. For EJ253 owners, it pays to check the coil pack for cracking and the plug leads for age‑hardening or high resistance. For EJ255 owners, pull the coil‑on‑plug units and check for heat‑browned boots, carbon tracking, or oil in the plug tubes from rocker cover leaks. A light smear of dielectric grease on boots helps future removal and seals out moisture. Always pair coil health with the basics: correct spark plugs (heat range and gap per the service manual), clean earths, and sound battery voltage.

Common clues that it’s time to test or replace include rough idle, hard starts, a stumble under load, worse fuel use, or a flashing check‑engine light with misfire codes (P0301–P0304) or coil circuit faults (P0351–P0354). Don’t keep driving on a misfire — unburnt fuel can cook the catalytic converter. If testing is needed, follow the Subaru service manual for proper resistance checks on the EJ253 coil pack and scope‑based checks or known‑good swap testing on COP units. Use quality OEM‑equivalent parts and avoid mixing old and new leads on coil‑pack cars. When refitting, clip connectors until they click and route leads neatly away from hot exhaust bits under the bonnet.

• Service tip: inspect coils/boots and leads at each plug change (often around 100,000 km with iridium plugs).
• Keep water out of the plug wells, avoid pressure‑washing directly around the coils.
• If one COP fails on an EJ255, consider proactively checking the others the same age.

Popular questions

Does the 2007 Forester have one ignition coil or four?

It depends on the engine. The 2.5‑litre non‑turbo EJ253 runs a single four‑tower coil pack with spark plug leads. The turbo EJ255 (XT) uses four separate coil‑on‑plug units, one per cylinder, mounted directly over each spark plug.

How often should 2007 Forester ignition coils be replaced?

They’re not a scheduled replacement item. Coils are typically replaced only when they show faults. As part of regular servicing, check coil housings/boots and wiring, and replace spark plugs on time. Many coils last well past 150,000–250,000 km, but heat, oil contamination, and age can shorten life.

What are the signs of a failing ignition coil, and is it safe to drive?

Look for rough idle, hesitation, hard starts, poor fuel economy, and a check‑engine light with misfire or coil circuit codes. It’s best not to keep driving with an active misfire — unburnt fuel can damage the catalytic converter. Get it tested and sorted promptly.