Parts for your 2015 Subaru Impreza-Oil pump

2015 Subaru Impreza Oil Pump: What It Does and How to Look After It

Based on technical sources including the Subaru Factory Service Manual for the 2015MY Impreza (FB20 engine, Lubrication section) and the Subaru Genuine Parts Catalogue (Group 15, Oil Pump Assy), the 2015 Subaru Impreza absolutely uses an engine oil pump. It’s a crankshaft-driven internal gear (trochoid) pump integrated into the timing chain/front cover, making it a critical component of the engine’s lubrication system.

On this Impreza, the oil pump’s job is to pull oil from the sump, pressurise it, and feed it through galleries to bearings, camshafts, the timing chain, and other moving bits. That oil film prevents metal-on-metal contact, carries away heat, and helps keep everything clean. Without good oil pressure, the engine won’t last long under the bonnet.

While the oil pump isn’t a routine service item like a filter, caring for it is baked into regular servicing. Using the correct oil grade and changing oil and filter on time are the biggest protectors of pump life. Sludgy or low oil can starve the pump, score its rotors, and drop pressure. Subaru’s manual also highlights correct sealing and priming procedures if the pump/front cover is ever removed.

If replacement is needed (usually due to wear, contamination, or damage), it’s a more involved job because the pump is built into the front cover. A workshop will typically:

• Drain oil and coolant, remove belts and crank pulley, then pull the timing chain/front cover.
• Inspect the strainer and O-ring, pump rotors, and front main seal