For 2024 the Subaru Impreza comes with two engines. The base is a 2.0-liter horizontally opposed “Boxer” four-cylinder engine with 152 horsepower and 145 pound-feet of torque for Base and Sport Models. On the RS model we have here is featured an identical looking 2.5-liter version with 182 horsepower and 178 pound-feet of torque, a significant increase over the standard 2.0-liter engine.
Here it’s mated to the “Lineartronic” continuously variable transmission and features Subaru’s trademark “symmetrical” all-wheel drive.
EPA fuel economy ratings are similar to the smaller engine with 26 mpg city, 33 mpg highway and 29 mpg combined – only 1 mpg different. The 2.5-liter engine is rated for regular unleaded fuel and employs an idle-start-stop system to help it achieve better fuel-economy and lower emissions.
Following the airflow, the engine breathes through a snorkel located at the top of the front radiator support. Air flows back into the filter box located at the front passenger side of the engine and then rearward to a single bore throttle-body.
The composite plastic intake manifold then divides the airflow to either side of the flat four-cylinder engine’s two cylinder bays. The engine features full aluminum construction of block and heads. Two cams on each head feature variable timing.
Exhaust exits the heads at the bottom of the engine on both sides and immediately into the catalyst system which largely cannot be seen from the engine compartment. You can however see behind the engine the front half of the transmission and axle shafts.
In spite of being tightly packed, the engine compartment is laid out well for service and maintenance. The engine oil dipstick is located on top passenger side of the engine right up in front. Looking down below, a single serpentine belt provides for all of the accessories and shows plenty of room for access when it comes time to replace it.
At the driver side front of the engine is the oil filler cap and also the oil filter itself for easy access. Bonus. Located nearby are also the windshield washer and engine coolant reservoirs. Behind these are the 12V battery which is also easy to access and service.
Over the driver side wheel well is the main fuse box which can be accessed by pressing a tab at the rear and front. Inside you will find a small fuse removal tool provided at the fuse block in addition to a few additional fuses stowed in the cover just in-case. The engine control unit (ECO) is located adjacent to the fuse box.
The brake fluid reservoir also located at the driver side rear of the engine bay and requires no gymnastics to get to. Notable underneath is its electronic power brake motor unit. Other braking components under the hood include the ABS control unit, which typically requires no service or maintenance.
Changing your air filter is done at the passenger side front of the engine bay by simply removing two clips, pushing the box open and lifting it out. We have a separate video on that linked down below in the information section.
Lastly, looking forward you will see dual electric cooling fans at the radiator. Always keep hands clear even when the engine is powered off.