What are the differences between TSI, FSI, and TFSI?

[MacAubrey]

The differences between Audi FSI and TFSI are as follows: 1. Different principles: The FSI engine uses an electronic chip to precisely control the amount of fuel injected into the cylinder for combustion through calculation and analysis, thereby improving the fuel mixture ratio and enhancing engine efficiency. The TFSI engine utilizes the high-temperature and high-pressure exhaust gases from the engine to drive the turbine at high speed, compressing the intake air with the intake turbine, while the computer increases the fuel injection volume. Combined with high-density intake air, it improves engine efficiency without changing the displacement. 2. Different technologies: The FSI engine is a direct-injection engine that employs stratified fuel combustion technology. The TFSI engine is a turbocharged direct-injection engine, combining the features of both FSI and TSI engines. 3. Different effects: FSI can directly inject fuel into the combustion chamber, reducing the engine's heat loss, thereby increasing output power and lowering fuel consumption, which benefits both fuel economy and performance. The TFSI engine incorporates both turbocharging and stratified combustion, combining the advantages of FSI and TSI engines.