For 2024 the Hyundai Sonata Hybrid is significantly refreshed but offers the same 2.0-liter direct-injected four-cylinder engine and hybrid drive system found under the hood since 2019. The gasoline engine itself has 150 horsepower and 139 pound-feet of torque.
Sandwiched between the engine and its conventional 6-speed automatic transmission is a pancake shaped electric motor assembly with 51 horsepower and 151 pound-feet of torque. It’s powered by an air-cooled 1.62 kWh Lithium-Ion battery pack located inside the passenger compartment under the back seat.
Also under the hood is a belt-driven starter motor generator which starts the engine and can generate power for the battery system. The entire system is rated at 192 combined horsepower. It’s available only with FWD which has an EPA rating of 44 mpg city, 51 mpg highway and 47 mpg combined.
Following the airflow, the intake charge starts at the top rear of the radiator and flows through a snorkel to a conventional air-filter box located at the passenger side of the engine bay. From there it travels around the rear of the engine through a tube to the throttle body at the front of the engine down low at the entrance to its composite plastic intake manifold.
The air then travels up into the combustion chambers which feature four vales per cylinder and variable valve timing. With the engine sound cover removed you can see the four spark plug coil packs atop the engine. Because this has direct fuel-injection most of the fuel hardware is hidden.
Routine maintenance on the Hyundai Sonata Hybrid is relatively identical to that of any normal gasoline powered vehicle. Caution however is to be taken with all of the orange wiring harnesses and their connections as handle up to 270 volts and are not intended to be user serviceable anyway.
Accessing the air-filter is easy, simply pop a few clips on the top of the air box at the passenger side of the engine compartment to get in and replace it. Windshield washer fluid is found just ahead of it with the bright blue cap.
Filling the oil be done directly at the top of the engine with or without the sound cover pulled off the cap located in plain sight. The oil dipstick is notable by the bright red handle nearby at the front of the engine.
There are two coolant reservoirs. One is for the hybrid power system, which can be found at the front of the engine compartment at the drive side atop the transmission and to the right of the main hybrid power converter and control unit. The main engine coolant reservoir is at the driver side firewall. Both use the same fluid.
Brake fluid can be checked at the firewall at its reservoir mounted atop its electronic brake control unit. Though it is not user serviceable, the main engine computer or ECU can be found just ahead of the brake fluid and coolant reservoirs.
The main consumer grade fuse box is located at the driver side of the engine bay ahead of the strut tower. It is accessed by popping a couple clips and a fuse removal tool can be found inside. Also located here is a 12V access post.
The 12V battery itself is actually an integrated part of the hybrid battery pack assembly located under the rear seat and is not a conventional battery type requiring traditional maintenance procedures.