Parts for your 2009 Subaru Impreza-Fuel pump

2009 Subaru Impreza fuel pump — purpose, care and when to replace

Technical sources confirm the 2009 Subaru Impreza is fitted with a fuel pump and absolutely relies on it. The Subaru Factory Service Manual for the 2008–2011 GE/GH Impreza (Fuel Injection/Fuel Delivery sections), Subaru’s Electronic Parts Catalogue for the same model years, and common workshop manuals all document an electric in-tank pump module used on petrol models, and an in-tank lift/supply pump feeding the high-pressure system on diesel variants.

On a 2009 Subaru Impreza, the fuel pump’s job is simple but critical: move fuel from the tank to the engine at the correct pressure and volume. Petrol models use a returnless in-tank electric pump and integrated filter/strainer to feed the injectors at stable pressure, while diesel versions use an in-tank supply pump that feeds the high-pressure pump for the common-rail system. Without a healthy pump, the Impreza can be hard to start, stumble under load, or cut out on hills and hot days.

Good care goes a long way. Keeping at least a quarter tank helps cool and lubricate the pump, especially in Aussie and Kiwi summer heat. Sticking with quality fuel and avoiding long-term storage on stale petrol reduces varnish that can seize the pump or clog the strainer. Most pump modules also have O-rings and a tank seal that dislike being disturbed repeatedly, so plan to renew seals when the module’s removed.

Signs it’s time to test or replace include:

• Long crank, intermittent stalling, or loss of power at highway speeds
• High-pitched whine from the tank area
• Low fuel pressure on a gauge, or lean fault codes under load

As part of servicing, it’s smart to pressure-test the system if any of the above shows up, or around higher mileages. Many 2009 Impreza petrol models have the primary filter within the pump module