What drives the turbine wheel of the turbocharger?

• A. Crankshaft
• B. Engine exhaust gases
• C. Air intake
• D. Fuel injectors

Answer: (B)

The turbine wheel is driven by the engine’s exhaust gases. When exhaust leaves the cylinders, it is hot and fast and flows through the turbine side of the turbocharger, transferring its energy to spin the turbine wheel. That rotation, through a shaft, also spins the compressor wheel on the opposite side, squeezing incoming air and boosting intake pressure for more efficient combustion and more power. The exhaust energy is the source that powers the turbine; the crankshaft, the air intake, and the fuel injectors all serve other roles—crankshaft drives the piston motion, air intake supplies air for combustion, and fuel injectors deliver fuel, but none of them directly drive the turbine.