Parts for your 2004 Subaru Forester-Starter motor

2004 Subaru Forester starter-motor — what it does and how to look after it

There’s no debate here: a starter-motor is absolutely fitted and relevant to the 2004 Subaru Forester. This is confirmed in the Subaru Factory Service Manual for the 2004 Forester (Starting System section), Subaru Technical Information System (STIS), and Denso application catalogues for the EJ25-powered Forester models. It’s a conventional 12‑volt, gear‑reduction starter that engages the ring gear on the flywheel or flexplate to crank the engine.

On a 2004 Forester, the starter-motor’s whole job is to spin the EJ25 quickly enough for fuel and spark to take over. A solenoid pushes the pinion into the ring gear, the motor cranks, and as soon as the engine fires, the pinion retracts. It’s used on both manual and auto transmissions, with no programming or relearn required after replacement.

As part of regular servicing, it’s worth giving the starter a bit of attention. Under the bonnet, keep battery terminals clean and tight, and make sure the main starter feed and earth straps are corrosion-free. If cranking sounds lazy, do a voltage drop test across the positive and ground paths while cranking, high drop points to cables, terminals, or the solenoid contacts. Listen for tell-tales like a single click (solenoid/voltage issue), rapid clicking (weak battery), slow crank (brushes, worn contacts, tired motor), or grinding (engagement or ring gear concerns).

Replacement is straightforward for a home mechanic with basic tools, or a quick job for a workshop. Disconnect the battery negative first. Access is typically from above by removing the air intake duct/box, or from underneath on stands. The unit is secured to the bellhousing with two bolts and has a main battery cable plus a small trigger wire. Refit in reverse, torque the fasteners to the Subaru spec from the service manual, and keep any heat shields and cable clips in place. No shims are used on this model, and no ECU programming is needed.

Quality matters: a new or reputable remanufactured Denso-type unit generally outlasts bargain options. If the vehicle’s nudging high kilometres and cranking has become inconsistent, pre-emptive replacement can save roadside grief. Also keep an eye on any oil leaks—oil wicking onto the starter can shorten its life.

• Common service checks: battery health, terminal condition, cable voltage drop, and starter mounting/earths.
• Typical lifespan: many last well past 200,000 km with clean electrics and good battery maintenance.

Popular questions

Where is the starter-motor on a 2004 Forester?
It’s mounted at the rear of the engine on top of the transmission bellhousing, beneath the intake area. Most techs access it from above by removing the air intake duct or airbox, or from below with the vehicle safely supported.

Can the original starter be rebuilt, or should it be replaced?
The factory unit is typically a Denso design, which can often be rebuilt with new brushes and solenoid contacts. For many owners, a quality reman or new unit is the quickest, most reliable fix—especially if the armature, bushings, or drive are worn.

What are the signs my 2004 Forester’s starter is failing?
Slow cranking, a single click with no crank, intermittent no‑start when hot, or grinding noises during start are common clues. Rule out a weak battery and corroded terminals first—if those are good, the starter or its solenoid is likely due.