Parts for your 2009 Subaru Impreza-Power steering pump

2009 Subaru Impreza Power Steering Pump

For the 2009 Subaru Impreza, a power-steering pump is absolutely relevant and fitted. Technical references including the Subaru Factory Service Manual for MY2009 Impreza (GE/GH/GR platform, Steering – Power Steering System) and Subaru’s electronic parts catalogue for 2009 list a belt-driven, hydraulic vane-type power-steering pump supplying the rack-and-pinion. Subaru moved many models to electric power steering in later generations, but the 2009 Impreza range (including WRX and STI) uses conventional hydraulic assist with a pump under the bonnet.

The pump’s job is straightforward: it pressurises fluid so the steering rack gets a helpful shove, making low-speed manoeuvres a breeze while keeping decent road feel at higher speeds. On a 2009 Impreza, it’s driven by the accessory belt, drawing fluid from the reservoir and sending it through the system to assist every turn of the wheel.

As part of regular servicing, it’s smart to give the power-steering system a once-over. Subaru specifies ATF (Dexron III) in this model’s power steering—check the cap and owner’s manual to be sure. Under the bonnet, look for dampness or weeping around the pump, hoses and fittings, and listen for a whine that rises with engine rpm, especially when cold. Also check belt condition and tension, a glazed or loose belt can make the pump noisy and the steering heavy.

Signs it may be time for attention include:

• Whine or groan from the pump, especially on cold start or at parking speeds
• Foamy, dark or burnt-smelling fluid in the reservoir
• Heavier-than-usual steering effort or intermittent assist
• Leaks around the pump, hose unions or reservoir

Preventative care is simple: inspect fluid at every service, and if it’s discoloured or contaminated, have it exchanged. Many technicians in Australia and New Zealand recommend a fluid refresh around 60,000–100,000 kilometres, or earlier if symptoms show.

When replacement is needed, quality reman or new pumps are available. It’s good practice to replace the suction-side O-ring at the pump inlet and any perished hoses at the same time, these small seals are a common source of air ingestion and cold-start whine on this era of Subaru. After fitting, bleed the system properly: fill with the correct ATF, raise the front wheels, turn lock-to-lock slowly with the engine off to purge air, then repeat with the engine running while topping up. Avoid holding full lock for more than a couple of seconds. Re-check fluid level and for leaks after a short drive. Done right, the steering stays quiet, light, and predictable.

Popular questions about the 2009 Subaru Impreza power-steering pump

What fluid should be used in the 2009 Impreza’s power steering?
Subaru specifies ATF (Dexron III) for the power-steering system on the 2009 Impreza. Don’t mix in generic “power-steering fluid” unless it explicitly states compatibility. Always confirm on the reservoir cap and in the owner’s manual.

Using the correct fluid helps prevent pump noise, protects seals, and maintains consistent steering feel in hot and cold conditions.

How is the power-steering system bled after pump replacement?
Fill the reservoir with the correct ATF, raise the front wheels off the ground, and slowly turn the steering from lock to lock 10–15 times with the engine off. Top up as air purges. Then start the engine and repeat the slow lock-to-lock movements, keeping the fluid level between the marks.

Avoid holding the wheel hard against the stops, and keep an eye out for foaming. Once the fluid runs clear and quiet, lower the car, road test, and recheck the level.

Why does my 2009 Impreza’s pump whine on cold mornings?
Common causes are a loose/glazed drive belt, low fluid level, or tiny air leaks at the pump’s suction O-ring or hose clamps. As the fluid warms, the noise can fade, but it’s a sign to act.

Replacing the suction-side O-ring, correcting belt tension, and refreshing old fluid typically cures the whine and protects the pump from premature wear.